Answer correctly and 40 points. Thx. Will report if wrong. ASAP plz! Thx!

Answer Correctly And 40 Points. Thx. Will Report If Wrong. ASAP Plz! Thx!

Answers

Answer 1

Answer:

-7

Step-by-step explanation:

if you multiply by 7 positive it wont work because u cant cancel 7x out and a fraction wont work because theres no fraction involved in this so ur answer is A


Related Questions

Why can you use cross products to solve the proportion StartFraction 18 over 5 EndFraction = StartFraction x over 100 EndFraction for x?

Answers

45
djekdkdkfkfkktkffk

Answer:

45

Step-by-step explanation:

In the accompanying diagram of isosceles triangle ABC, overline AB cong overline BC , BAC =X , and m angle ABC=3x+70

Answers

Answer:

x = 22

Step-by-step explanation:

In order to solve this, we need to understand that in an isosceles triangle the two angles that are located at its base are equal to each other.

base - (the side that is not one of the two sides that are equivalent to each other)

Knowing this we can see that ∠ACB will equal ∠BAC, therefore ∠ACB will be equal to x°. Since the sum of all inner angles of a triangle is equal to 180°, we can make the following equation...

x° + x° + (3x + 70)° = 180°

2x° + 3x° + 70° = 180°

5x° = 180° - 70°

5x° = 110°

x° = 110° / 5

x° = 22°

x = 22

Therefore, x = 22.

3. The size of a red blood cell is 0.000007 m and the size of a plant
cell is 0.0000127 m. Compare these two.​

Answers

Given:

Size of a red blood cell = 0.000007 m

Size of a plant cell = 0.0000127 m

To find:

The comparison of these two values.

Solution:

We have,

Size of a red blood cell = 0.000007 m

Size of a plant cell = 0.0000127 m

Clearly, [tex]0.0000127>0.000007[/tex]. Now, the difference between these two values is:

[tex]0.0000127-0.000007=0.0000057[/tex]

Therefore, the size of a plant cell is 0.0000057 m more than the size of a red blood cell.

Will give brainliest answer please give explanation


If this block dropped into 23.0mL of water, what will the new volume be?

Answers

The information for volume of the block is missing.

Volume of block X 1ml/1cm^3 = x mL

23.0 mL + x = final answer mL

Find the value of x. Round to the nearest tenth. Chords and Arcs​

Answers

9514 1404 393

Answer:

  4.1

Step-by-step explanation:

x is the short leg of a right triangle with hypotenuse 8.8 cm and longer leg 7.8 cm. Its measure is found using the Pythagorean theorem:

  x^2 +7.8^2 = 8.8^2

  x^2 = 77.44 -60.84 = 16.60

  x = √16.6

  x ≈ 4.1

Which answers describe the shape below? Check all that apply.
A. Trapezoid
B. Parallelogram
C. Rhombus
D. Rectangle
E. Quadrilateral
F. Square

Answers

Answer:

B, C, and E

Step-by-step explanation:

The fracture strength of a certain type of manufactured glass is normally distributed with a mean of 509 MPa with a standard deviation of 17 MPa. (a) What is the probability that a randomly chosen sample of glass will break at less than 509 MPa

Answers

Answer:

0.5 = 50% probability that a randomly chosen sample of glass will break at less than 509 MPa

Step-by-step explanation:

Normal Probability Distribution

Problems of normal distributions can be solved using the z-score formula.

In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the z-score of a measure X is given by:

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.

Mean of 509 MPa with a standard deviation of 17 MPa.

This means that [tex]\mu = 509, \sigma = 17[/tex]

What is the probability that a randomly chosen sample of glass will break at less than 509 MPa?

This is the p-value of Z when X = 509. So

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

[tex]Z = \frac{509 - 509}{17}[/tex]

[tex]Z = 0[/tex]

[tex]Z = 0[/tex] has a p-value of 0.5

0.5 = 50% probability that a randomly chosen sample of glass will break at less than 509 MPa

The salaries of 235 nurses were recorded and analyzed. The analyst later found that the highest salary was incorrectly recorded as 10 times the actual amount. After the error was corrected, the report showed that the corrected value was still higher than any other salary. Which sample statistic must have changed after the correction was made?

Answers

The sample statistic that must have changed after the correction was made is mean. Because mean is based on all the observation in the data. So changing any value in the data will impact mean.

Changing the highest salary in the data will have no impact on median because median lies at the center of data.

Changing the highest salary in the data will have no impact on mode because mode is the most frequently occurring value in the data.

Changing the highest salary in the data will have no impact on minimum because minimum is the smallest value in the data.

Hence the only statistic which will change is mean.

Answer: A-Mean

Step-by-step explanation:

A.) Mean

B.) Median

C.)  Mode

D.)  Minimum

which of the following sets represents the tangeof the function shown? {(-3,4),(5,11),(9,-1),(10,13)}​

Answers

Answer:  Range = {4, 11, -1, 13}

Explanation:

The range is the set of y outputs of a relation. So we just list the y coordinates of the points shown.

We could sort the values to get {-1, 4, 11, 13}, but order doesn't matter in a set. So this step is optional.

What is the longest side of a right angled triangle called?

Answers

Answer:

The hypotenuse

Estimate the student's walking pace, in steps per minute, at 3:20 p.m. by averaging the slopes of two secant lines from part (a). (Round your answer to the nearest integer.)

Answers

This question is incomplete, the complete question is;

A student bought a smart-watch that tracks the number of steps she walks throughout the day. The table shows the number of steps recorded (t) minutes after 3:00 pm on the first day she wore the watch.

t (min)       0          10          20         30         40

Steps   3,288    4,659    5,522    6,686    7,128

a) Find the slopes of the secant lines corresponding to the given intervals of t.

1) [ 0, 40 ]

11) [ 10, 20 ]

111) [ 20, 30 ]

b) Estimate the student's walking pace, in steps per minute, at 3:20 pm by averaging the slopes of two secant lines from part (a). (Round your answer to the nearest integer.)

Answer:

a)

1) for [ 0, 40 ], slope is 96

11) for [ 10, 20 ],  slope is 86.3

111) for  [ 20, 30 ], slope is 116.4

b) the student's walking pace is 101 per min

Step-by-step explanation:

Given the data in the question;

t (min)       0          10          20         30         40

Steps   3,288    4,659    5,522    6,686    7,128

SLOPE OF SECANT LINES

1) [ 0, 40 ]

slope =  ( 7,128 - 3,288 ) / ( 40 - 0

= 3840 / 40 = 96

Hence slope is 96

11)  [ 10, 20 ]

slope = ( 5,522 - 4,659 ) / ( 20 - 10 )

= 863 / 10 = 86.3

Hence slope is 86.3

111)  [ 20, 30 ]

slope = ( 6,686 - 5,522 ) / ( 30 - 20 )

= 1164 / 10 = 116.4

Hence slope is 116.4

b)

Estimate the student's walking pace, in steps per minute, at 3:20 pm by averaging the slopes of two secant lines from part .

Since this is recorded after 3:00 pm

{ 3:20 - 3:00 = 20 }

so t = 20 min

so by average;

we have ( [ 10, 20 ] + [ 20, 30 ] ) /2

⇒ ( 86.3 + 116.4 ) / 2

= 202.7 /2

= 101.35 ≈ 101

Therefore, the student's walking pace is 101 per minutes

What is the y-intercept of the line given by y=4x - 6

Answers

The y-intercept for this line is (0, -6)

Answer:

y= -6

Step-by-step explanation:

the y-intercept is -6, which corresponds to point (0,-6)

remember that you're using the

y=mx+b format of an equation of a line where b is the y-intercept.

Also, if you make x=0, y will be -6.

Can someone help me please..

Answers

D, company b has a larger mean than company a

(x+a)(x-a) = x² -25 then what is the value of a ?​

Answers

Answer:

The value of A is 5

......

[tex]\huge{\boxed{\boxed { ⎆ Answer :- }}} \ [/tex]

[tex](x + a)(x - a) = {x}^{2} - 25[/tex]

Use, the algebraic identity ↦

[tex](a + b)(a - b) = {a}^{2} - {b}^{2} [/tex]

So,

[tex](x + a)(x - a) = {x}^{2} - 25 \\ \\ ⟹ \sqrt{25} = 5[/tex]

↦So, the value of a is 5.

ʰᵒᵖᵉ ⁱᵗ ʰᵉˡᵖˢ

꧁❣ ʀᴀɪɴʙᴏᴡˢᵃˡᵗ2²2² ࿐

If a+bi, where b is not equal to 0, is a complex zero of a polynomial with real coefficients, then so is its _____ , a-bi.

a.) linear factorization
b.) irreducible factor
c.) reducible factor
d.) complex factor
e.) fundamental theorem
f.) conjugate​

Answers

Hello,

answer f: conjugate

if all coefficients are real and a+ib a zero, its conjgate a-ib is also a zero.

A regression was run to determine whether there is a relationship between hours of tv watched per day(x) and number of sit-ups a person can do (y). The results of the regression are given below. Use this to predict the number of sit-ups a person who watches 11 hours of tv can do
Y=ax+b
A=-1.341
B=32.234
R=-0.896

Answers

Answer:

17

Step-by-step explanation:

Given the regression model :

Y=ax+b

x = Hours of TV watched per day

y= number of sit-ups a person can do

A=-1.341

B=32.234

Y = - 1.341x + 32.234

Predict Y, when x = 11

Y = - 1.341(11) + 32.234

Y = −14.751 + 32.234

Y = 17.483

Hence, the person Cann do approximately 17 sit-ups

In 2013, the Public Religion Research Institute conducted a survey of 1,033 adults, 18 years of age or older, in the continental United States. One of the questions on their survey was as follows:

Answers

Answer:

Probability[Number of people from church] = 0.26 (Approx.)

Step-by-step explanation:

Given:

Total number of adult in survey = 1,033

Missing information:

Number of people from church = 269

Find:

Probability[Number of people from church]

Computation:

Probability of an event = Number of favourable outcomes / Number of total outcomes

Probability[Number of people from church] = Number of people from church / Total number of adult in survey

Probability[Number of people from church] = 269 / 1,033

Probability[Number of people from church] = 0.2604

Probability[Number of people from church] = 0.26 (Approx.)

The cost of 5 gallons of ice cream has a variance of 64 with a mean of 34 dollars during the summer. What is the probability that the sample mean would differ from the true mean by less than 1.1 dollars if a sample of 38 5-gallon pails is randomly selected

Answers

Answer:

0.5587 = 55.87% probability that the sample mean would differ from the true mean by less than 1.1 dollars.

Step-by-step explanation:

To solve this question, we need to understand the normal probability distribution and the central limit theorem.

Normal Probability Distribution:

Problems of normal distributions can be solved using the z-score formula.

In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the z-score of a measure X is given by:

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.

Central Limit Theorem

The Central Limit Theorem establishes that, for a normally distributed random variable X, with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean [tex]\mu[/tex] and standard deviation [tex]s = \frac{\sigma}{\sqrt{n}}[/tex].

For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.

The cost of 5 gallons of ice cream has a variance of 64 with a mean of 34 dollars during the summer.

This means that [tex]\sigma = \sqrt{64} = 8, \mu = 34[/tex]

Sample of 38

This means that [tex]n = 38, s = \frac{8}{\sqrt{38}}[/tex]

What is the probability that the sample mean would differ from the true mean by less than 1.1 dollars ?

P-value of Z when X = 34 + 1.1 = 35.1 subtracted by the p-value of Z when X = 34 - 1.1 = 32.9. So

X = 35.1

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

By the Central Limit Theorem

[tex]Z = \frac{X - \mu}{s}[/tex]

[tex]Z = \frac{35.1 - 34}{\frac{8}{\sqrt{38}}}[/tex]

[tex]Z = 0.77[/tex]

[tex]Z = 0.77[/tex] has a p-value of 0.77935

X = 32.9

[tex]Z = \frac{X - \mu}{s}[/tex]

[tex]Z = \frac{32.9 - 34}{\frac{8}{\sqrt{38}}}[/tex]

[tex]Z = -0.77[/tex]

[tex]Z = -0.77[/tex] has a p-value of 0.22065

0.77935 - 0.22065 = 0.5587

0.5587 = 55.87% probability that the sample mean would differ from the true mean by less than 1.1 dollars.

Find a degree 3 polynomial with real coefficients having zeros 1
and 2−2i and a lead coefficient of 1. Write P in expanded form. Be sure to write the full equation, including P(x)=

Answers

9514 1404 393

Answer:

  P(x) = x³ -5x² +12x -8

Step-by-step explanation:

If the coefficients are real, then the complex roots must be conjugates. The third root is 2+2i. For root r, (x -r) is a factor, so the factorization is ...

  P(x) = (x -1)(x -2 +2i)(x -2 -2i) = (x -1)((x -2)² +4) = (x -1)(x^2 -4x +8)

Expanding further, we find ...

  P(x) = x³ -5x² +12x -8

In a survey, 24 people were asked how much they spent on their child's last birthday gift. The results were roughly bell-shaped with a mean of $42 and standard deviation of $2. Construct a confidence interval at a 98% confidence level.

Answers

Answer:

The 98% confidence interval for the mean amount spent on their child's last birthday gift is between $40.98 and $43.02.

Step-by-step explanation:

We have the standard deviation for the sample, which means that the t-distribution is used to solve this question.

The first step to solve this problem is finding how many degrees of freedom, we have. This is the sample size subtracted by 1. So

df = 24 - 1 = 23

98% confidence interval

Now, we have to find a value of T, which is found looking at the t table, with 23 degrees of freedom(y-axis) and a confidence level of [tex]1 - \frac{1 - 0.98}{2} = 0.99[/tex]. So we have T = 2.5

The margin of error is:

[tex]M = T\frac{s}{\sqrt{n}} = 2.5\frac{2}{\sqrt{24}} = 1.02[/tex]

In which s is the standard deviation of the sample and n is the size of the sample.

The lower end of the interval is the sample mean subtracted by M. So it is 42 - 1.02 = $40.98.

The upper end of the interval is the sample mean added to M. So it is 42 + 1.02 = $43.02.

The 98% confidence interval for the mean amount spent on their child's last birthday gift is between $40.98 and $43.02.

A walking path across a park is represented by the equation y = -4x + 10. A new path will be built perpendicular to this path. The paths will intersect at the point (4, -6). Identify the equation that represents the new path.

Answers

Answer:  [tex]y=\frac{1}{4}x-7[/tex]

Step-by-step explanation:

The perpendicular slope of the line(m) = [tex]-\frac{1}{m}[/tex]:

m = -4 ⇒ [tex]-\frac{1}{m} =-\frac{1}{(-4)} =\frac{1}{4}[/tex]

The function formula is y = mx + b, where the y-intercept(b) is found by substituting in the values of a point on the line ⇒ (4, -6):

[tex]y=\frac{1}{4}x+b\\-6=\frac{1}{4}(4)+b\\-6=1+b\\b=-6-1=-7[/tex]

So the perpendicular equation is [tex]y=\frac{1}{4}x-7[/tex].

The linear equation Y = a + bX is often used to express cost formulas. In this equation:_________
a) the b term represents variable cost per unit of activity.
b) the a term represents variable cost in total.
c) the X term represents total cost.
d) the Y term represents total fixed cost.

Answers

Ruben hjhffddssz Chicago

I’ll give brainliest

Answers

Answer:

A

Step-by-step explanation:

From f(x) to k(x), the graphed parabola is stretched and wider.

Answer: Choice B) Vertically compressed by a factor of 8.

Explanation:

Consider a point like (8,64) which is on f(x).

If we plug in x = 8 into k(x), then we would get k(8) = 8. The old output y = 64 is now y = 8. This is an example of a vertical compression of 8. It's 8 times smaller in the vertical direction compared to what it used to be. This is because the k(x) outputs are 1/8 those of the f(x) outputs.

Effectively we have k(x) = (1/8)*f(x).

Another example would be x = 16 leading to y = 256 on f(x). For k(x), we have x = 16 lead to y = 32

Refer to the graph below.

Use the formula for the volume of a cube given by
V = s3
where s is the length of one of the sides. This formula yields the volume in cubic units.
Suppose a certain sugar cube has a side that measures 5/9 inches per side. What is the volume of this sugar cube (in in3)? Round the result to three decimal places.

Answers

Answer:

The volume of the cube is 0.171 cubic inches.

Step-by-step explanation:

The volume of a cube given by :

[tex]V=s^3[/tex]

Where

s is the length of one of the sides.

We need to find the volume of the sugar cube if its side is 5/9 inches per side.

So,

[tex]V=(\dfrac{5}{9})^3\\\\V=0.171\ inches^3[/tex]

So, the volume of the cube is 0.171 cubic inches.

Ed decided to build a storage box. At first, he was planning to build a cubical box with edges of length n inches. To increase the amount of storage, he decided to make the box 1 inch taller and 2 inches longer while keeping its depth at n inches. The volume of the box Ed built has a volume how many cubic inches greater than the box he originally planned to build?

Answers

Answer:

The new volume is 3n^2+2n inches greater.

Step-by-step explanation:

Volume of a cube = s^3 where s is side of cube

Original volume = n^3

Volume of a Rectangular Prism = LBH

New Volume = (n+1)(n+2)(n)= n^3+3n^2+2n

DIfference = New- original = 3n^2+2n

The diagram shows that `/_A cong /_D` and `bar(AB) cong bar(DE)`. Which other statement do you need to prove triangle congruency through the SAS criterion?
A. /_C cong /_F
B. bar(BC) cong bar (EF)
C. /_B cong /_E
D. bar(AC) cong bar(DF)

Answers

Answer:

Option D

Step-by-step explanation:

In the given triangles ΔABC and ΔDEF,

∠A ≅ ∠D

AB ≅ DE

By SAS property of congruence of two triangles,

Two sides and the included angle of one triangles should be congruent to corresponding two sides and the included angle of the other triangle.

Therefore, AC ≅ FD will be the desired property to prove the given triangles congruent.

Option D will be the correct option.

Answer:

Step-by-step explanation:

fill in the blink

Given ,Simplify ,BC=EF ,Multiplication Property of Equality ,Substitution Property of Equality AC=DF DE+EF=DF Reflexive Property of Equality Transitive Property of Equality ,Segment Addition Postulate, Division Property of Equality ,Addition Property of Equality, Distributive Property, Subtraction Property of Equality

Answers

Answer:

see below

Step-by-step explanation:

[tex] \displaystyle AB = DE[/tex]

[given]

[tex] \displaystyle \boxed{BC = EF}[/tex]

[given]

[tex] \displaystyle AB + BC = AC[/tex]

[segment addition Postulate]

[tex] \displaystyle \boxed{DE+ EF=DF}[/tex]

[segment addition Postulate]

[tex] \rm\displaystyle DE+ BC = AC \: \: \text{and} \: \: DE+ BC = DF[/tex]

[Substitution Property of Equality]

[tex] \displaystyle \boxed{AE= DE}[/tex]

[Proven]

Does anyone know the awnser please

Answers

Answer:

please which level is this

and also is it core maths or elective math

You want to make a playlist with all different songs. How many ways can you make a playlist of 16 songs if you must play Leavon, Dream on, Here Comes the Sun, and Clocks in that order?

Answer in permutations

Answers

Answer:  [tex]_{13} P _{13}[/tex]

Another acceptable answer is 13! where the exclamation mark is needed.

The numeric form is 6,227,020,800 which is a little over 6 billion.

==============================================================

Explanation:

Let's lump those four songs together to form a so called "mega song". So we treat those four items as one single item. This is ensure that those songs are played in the order we want. The other songs aren't treated this way.

We start with 16 songs and drop to 16-4 = 12 songs when taking out those four named songs. Then we add 1 to get 12+1 = 13 since we're adding in that "mega song" block.

---------------------------

So to recap so far, we've gone from 16 songs to 13 songs. The goal is to find out how many arrangements of 13 songs are possible. Order matters.

We'll use the nPr permutation function

[tex]_{n} P _{r} = \frac{n!}{(n-r)!}\\\\[/tex]

where in this case n = 13 and r = 13. Your teacher doesn't want you to evaluate this function. You simply need to state the symbolic form. So that's why we go from [tex]_{n} P _{r}[/tex] to [tex]_{13} P _{13}[/tex]

If you wanted to answer this in terms of factorial notation, then you could say this

[tex]_{n} P _{r} = \frac{n!}{(n-r)!}\\\\_{13} P _{13} = \frac{13!}{(13-13)!}\\\\_{13} P _{13} = \frac{13!}{(0)!}\\\\_{13} P _{13} = \frac{13!}{1}\\\\_{13} P _{13} = 13!\\\\[/tex]

So we can see that the notations [tex]_{13} P _{13}[/tex] and [tex]13![/tex] mean the exact same thing.

If you wanted to know the actual number of permutations, then,

13! = 13*12*11*10*9*8*7*6*5*4*3*2*1 = 6,227,020,800

which is a little over 6 billion permutations.


Work out the surface area of this sphere.
Give your answer to 1 decimal place.
Spheres
Surface area =
4tr?
6 cm

Answers

Answer:

452.2 cm

Step-by-step explanation:

A = 4πr²

A = 4 (3.14) (6)²

A = 4 (3.14) (36)

A = 452.16

A = 452.2 cm (nearest tenth)

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divide 18/7 by 8/26. Pls give the correct ans A rectangular tank 60 cm long and 50 cm wide is /5 full of water. When 24 liters of water are added, the water level rises to the brim of the tank. Find the height of the tank. (1 liter is 1000cm3 ) Which of the following is a correctly written algebraic equation? a + 0.2x5b - 5x + 2a- 3x = 0 The ____ contains app buttons that allow you to quickly run the File Explorer or Microsoft Edge apps. Escribe tres frases en tiempo presente con los verbos: correr, trabajar y viajar. A three-dimensional object's measurement(s) include which of the following?Check all that apply.A. WidthB. LengthC. HeightD. None of these Please help me with solving these. Id really appreciate your help. Thank you very much. Question is in the photo* i need help asap. rn Which formulas can be used to find the surface area of a right prism where p is the perimeter of the base, h is the height of the prism, BA is the area of bases, and LA is the lateral area? Check all that apply. A. SA = BA - LAB. SA = p + LA C. SA = BA + LA D. SA = BA + ph E. SA = 1 / BA + LA What is Nicaragua's capital city?MasayaManaguaOmetepeGallo Pinto Write the rule that describes the first transformation? RED > BLUE Offering direct online sales to consumers while also promoting wholesale and retail sales can result in Multiple select question. cannibalization of retailers' sales. a net loss of sales due to disgruntled dealers. a signal of the company's strong commitment to retailers. channel conflict. The pressure exerted at the bottom of a column of liquid is 30 kPa. The height of thecolumn is 3,875 m. What type of liquid is used? why are electrons in an atom involved in bonding Sounds effects _______. a. must be realistic in order to work successfully in a film b. must be added during filming, simultaneously to the action that is supposed to produce them c. need not be realistic but must coordinate with our imaginations d. are not made by devices not naturally part of the film's narrative 5- Observ el cartel y resolv calculando el m.C.M entre las cantidades. FRECUENCIA A Mar del Plata, cada 2 horas A Necochea , cada 4 horas A San Clemente, cada 6 horas a) Si acaba de partir un micro a cada destino, cuntas horas pasarn para que vuelvan a salir tres micros al mismo tiempo? it is represented by a small rectangle with curved corners and appears at the start and the end of a flowchart A hot-air balloon is rising upward with a constant speed of 2.85 m/s. When the balloon is 2.50 m above the ground, the balloonist accidentally drops a compass over the side of the balloon. How much time elapses before the compass hits the ground Si "m" es el lado mayor de un tringulo, dos cuyos ngulos interiores miden 30 y 60, entonces el permetro del tringulo es