THIS IS URGENT. PLEASE HELP. given AC=30, find the value if x, and the length of BC

They are both really the same. so they should hold the same. All that happened is one moved a 1/2 inch over to the length from the height.  

Answers:

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Explanation:

Problem 1

This is false because the A and B should swap places. It should be [tex](AB)^{-1} = B^{-1}A^{-1}[/tex].

The short proof is to multiply AB with its inverse [tex](AB)^{-1}[/tex]  and we get: [tex](AB)*(AB)^{-1} = (AB)*(B^{-1}A^{-1}) = A(B*B^{-1})*A^{-1} = A*A^{-1} = I[/tex]

The fact we get the identity matrix proves that we have the proper order at this point. The swap happens so that B matches up its corresponding inverse [tex]B^{-1}[/tex] and the two cancel each other out.

Keep in mind matrix multiplication is not commutative. So AB is not the same as BA.

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Problem 2

This statement is true if and only if AB = BA

(A+B)^2 = (A+B)(A+B)

(A+B)^2 = A(A+B) + B(A+B)

(A+B)^2 = A^2 + AB + BA + B^2

(A+B)^2 = A^2 + 2AB + B^2 ... only works if AB = BA

However, in most general settings, matrix multiplication is not commutative. The order is important when multiplying most two matrices. Only for special circumstances is when AB = BA going to happen. In general,  AB = BA is false which is why statement two breaks down and is false in general.

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Problem 3

This statement is true.

If A and B are invertible, then so is AB.

This is because both [tex]A^{-1}[/tex] and [tex]B^{-1}[/tex] are known to exist (otherwise A and B wouldn't be invertible) and we can use the rule mentioned in problem 1. Make sure to swap the terms of course.

Or you can use a determinant argument to prove the claim

det(A*B) = det(A)*det(B)

Since A and B are invertible, their determinants det(A) and det(B) are nonzero which makes the right hand side nonzero. Therefore det(A*B) is nonzero and AB has an inverse.

So if we have two invertible matrices, then their product is also invertible. This idea can be scaled up to include things like A^4*B^3 being also invertible.

If you wanted, you can carefully go through it like this:

and so on until you build up to A^4*B^3. Therefore, we can conclude that A^m*B^n is also invertible. Be careful about the order of multiplying the matrices. Something like A*AB is different from AB*A, the first of which is useful while the second is not.

So this is why statement 3 is true.

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Problem 4

This is false. Possibly a quick counter-example is to consider these two matrices

[tex]A = \begin{bmatrix}1 & 0\\0 & 1\end{bmatrix} \text{ and } B = \begin{bmatrix}-1 & 0\\0 & -1\end{bmatrix}[/tex]

both of which are invertible since their determinant is nonzero (recall the determinant of a diagonal matrix is simply the product along the diagonal entries). So it's not too hard to show that the determinant of each is 1, and each matrix shown is invertible.

However, adding those two mentioned matrices gets us the 2x2 zero matrix, which is a matrix of nothing but zeros. Clearly the zero matrix has determinant zero and is therefore not invertible.

There are some cases when A+B may be invertible, but it's not true in general.

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Problem 5

This is true because each A pairs up with an [tex]A^{-1}[/tex] to cancel out (similar what happened with problem 1). For more info, check out the concept of diagonalization.

In the third column, the sequence is: F, T, F, T

You flip whatever you see in the q column since ~q means "not q".

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In the fourth column is: T, T, T, F

The general form of p -> q is false if p is true while q is false; otherwise, it is true. So ~q -> p is false when ~q is true and p is false.

Answer:

AAS

Step-by-step explanation:

There are two congruent angles, but the congruent side is not included between the two angles.

Answer:

No.

Step-by-step explanation:

Translation is a type of rigid transformation. It simply moves the figure around the coordinate plane, so the size doesn't change.

Answer:

y=1.2x-3

Step-by-step explanation:

I had this as an rsm problem a few weeks ago and forgot how to solve it lol hope this helps

Answer:

142884, Answer,

Step-by-step explanation:

The first term of a GP is 7, the ratio is 3. What is the sum of the 7th and 10th term?

Solution: In the given GP, a = 7 and r = 3.

The sum of the 7th and the tenth terms

= T7 +T10 = ar^6 + ar^9 = ar^6[1+r^3]

= 7*3^6[1+3^3]

= 5103*28

= 142884, Answer,

please mark brainliest

The first term of geometric series is, a = 363/82

An sequence has the ratio of every two successive terms is a constant, is called a Geometric sequence.

Give that;

Sum of T₃ and T₇ of geometric series = 3267

And, common ratio(r) = 3

Hence, To find first term (a) we can use formula as;

Tₙ = arⁿ⁻¹

Now,  put the value on formula;

T₃ = a(3)³⁻¹

T₃ = (3)²a

And, T₇ = a(3)⁷⁻¹

T₇ = (3)⁶a

Since, T₃ + T₇ = 3267

Hence,

(3)²a + (3)⁶a = 3267

3²(a + 3⁴a) = 3267

(a + 3⁴a) =363

a + 81a = 363

82a = 363

a = 363/82

Thus, The first term of geometric series is, a = 363/82

Learn more about the geometric sequence visit:

https://brainly.com/question/25461416

#SPJ2

Consider the [tex]n[/tex]-th partial sum of a geometric series with first term [tex]a[/tex] and common ratio [tex]r[/tex] between consecutive terms. Then the sum of the first [tex]n[/tex] terms of this series is

[tex]S = a + ar + ar^2 + \cdots + ar^{n-1}[/tex]

Multiply both sides by [tex]r[/tex], then subtract [tex]rS[/tex] from [tex]S[/tex] and solve for [tex]S[/tex].

[tex]rS = ar + ar^2 + ar^3 + \cdots + ar^n[/tex]

[tex]S - rS = a - ar^n[/tex]

[tex]\implies S = \dfrac{a(1-r^n)}{1-r}[/tex]

In the given series, we have [tex]a=1[/tex] and [tex]r=2[/tex]; then the sum of the series with [tex]n=8[/tex] terms is

[tex]S = \dfrac{1-2^8}{1-2} = 2^8 - 1 = \boxed{255}[/tex]

Answer:

45.3 megabytes

Step-by-step explanation:

242 x 18.7%

= 242 x 0.187 = 45.254 = 45.3 megabytes

 [tex]\bold{Hello!}\\\bold{Your~Answer~Is~Below!}[/tex]

______________________________

 [tex]\bold{Solution~Steps:}[/tex]

[tex]1.)~Multiply~the~parenthesis:[/tex]

[tex]2.)~Subtract~the~parenthesis:[/tex]

[tex]3.)~Subtract~on~the~side~without~an~equal:[/tex]

______________________________

 [tex]\bold{Answer:}[/tex]

______________________________

 [tex]\bold{Hope~this~helps,}\\\bold{And~best~of~luck!}\\\\\bold{~~~~~~-TotallyNotTrillex}[/tex]

Answer:

Step-by-step explanation:

Answer:

i think it's b4

Step-by-step explanation:

Answer:

1+x it means I plus the rest

Answer:

(4, -1)

Step-by-step explanation:

Given:

C(1, -6)

D(7, 4)

Required:

Midpoint of CD using [tex] M(\frac{x_1 + x_2}{2}, \frac{y_1 + y_2}{2}) [/tex]

SOLUTION:

[tex] M(\frac{x_1 + x_2}{2}, \frac{y_1 + y_2}{2}) [/tex]

Let [tex] C(1, -6) = (x_1, y_1) [/tex]

[tex] D(7, 4) = (x_2, y_2) [/tex]

Thus:

[tex] M(\frac{1 + 7}{2}, \frac{-6 + 4}{2}) [/tex]

[tex] M(\frac{8}{2}, \frac{-2}{2}) [/tex]

[tex] M(4, -1) [/tex]

Answer:

[tex]\displaystyle y = -2x + 8[/tex]

Step-by-step explanation:

Perpendicular equations have OPPOCITE MULTIPLICATIVE INVERCE RATE OF CHANGES [SLOPES], so ½ becomes −2. Now, proceed with plugging the information into the Slope-Intercept Formula:

[tex]\displaystyle 2 = -2[3] + b \hookrightarrow 2 = -6 + b; 8 = b \\ \\ \boxed{y = -2x + 8}[/tex]

I am joyous to assist you at any time.

Answer:

96

Step-by-step explanation:

commom difference = d

a₆ + a₇ = 16

a₅ + a₈ = (a₆ - d) + (a₇ + d) = a₆ + a₇ = 16

a₄ + a₉ = (a₆ - 2d) + (a₇ + 2d) = a₆ + a₇ = 16

Similarly,

a₃ + a₁₀ = 16, a₂ + a₁₁ = 16, a₁ + a₁₂ = 16

so

a₁ + a₂ + ... + a₁₁ + a₁₂ = 6 x 16 = 96

Answer:

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

[tex]35000 \times \frac{15}{100} = 350 \times 15 = 5250[/tex]

Answer:

Slope = 20

y-intercept = 60

Step-by-step explanation:

Slope formula is given as [tex] m = \frac{y_2 - y_1}{x_2 - x_1} [/tex]

Pick two points on the line and use their coordinates. Let's pick (1, 80) and (2, 100).

Let,

[tex] (1, 80) = (x_1, y_1) [/tex]

[tex] (2, 100) = (x_2, y_2) [/tex]

Plug the values above into the formula for slope:

[tex] m = \frac{100 - 80}{2 - 1} = \frac{20}{1}} = 20 [/tex]

Slope of the graph is 20.

The y-intercept is the point where the line intercepts the y-axis. Thus, y-intercept = 60.

Answer:

The answer is 7680

Step-by-step explanation:

First you multiply 32 by 4(the usual formula) which gives you 128. However, the time changes the some things. So then you must multiply 128 by 60 (60 minutes in one hour). Which gives you 7680

hope i helped :D

Answer:

1.6 is how much each person gets

hope this will helpful to you

Answer:

undefined

Step-by-step explanation:

(y2-y1)/(x2-x1)

replacing x and y with the given value:

(-4-1)/(8-8)

-5/0

the slope is undefined because the run is 0

The weight of the new student is 27 kg.

Average weight

= total weight ÷total number of students

Let the total weight of the 35 students be y kg and the weight of the new student be x kg.

[tex]45 = \frac{y}{35} [/tex]

y= 35(45)

y= 1575 kg

New total number of students

= 35 +1

= 36

Total weight

= total weight of 35 students +weight of new students

= y +x

[tex]44.5 = \frac{y + x}{36} [/tex]

[tex]44.5 = \frac{1575 + x}{36} [/tex]

36(44.5)= 1575 +x

1602= x +1575

Subtract 1575 from both sides:

x= 1602 -1575

x= 27

Thus, the weight of the new student is 27 kg.

Answer:

you find the solution to each then arrange from smallest to largest and you'll get the answer

Answer:

D

Step-by-step explanation:

A: 2346

B: 357

C: 168

D: 1239

E: 12345

when put in order from smallest to largest, the order is:

C, B, D, A, E

The middle is D, so the answer is D.

Answer:

The conductor checked on the passengers 12 times.

Step-by-step explanation:

To find how many times the conductor checks on the passengers, you must do

8 divided by 2/3

because you have to find how many 2/3 (times checked by conductor) are in 8 hours.

8/1 ÷ 2/3

Switch the two numbers of 2/3 or find the reciprocal which is

3/2

and change ÷ to ×

Now solve.

8/1 x 3/2 =  24/2 (8x3=24 and 1x2=2)

which Simplified is

12/1 or 12

Check your answer:

12/1 x 2/3 = 24/3 = 8

The conductor checked on the passengers 12 times.

Answer:

fourth are in one half

Step-by-step explanation:

please mark me as brainlist please

well, a right-triangle will have one angle that is 90°, and using the pythagorean theorem, we also know that the longest side is really the root of the sum of the square of the other two.  After all that mouthfull let's check

[tex]\stackrel{longest}{16}~~ = ~~\sqrt{\underset{short}{13^2}~~ + ~~\underset{short}{4^2}}\implies 16=\sqrt{169+16} \\\\\\ 16=\sqrt{185}\implies 16^2=185\implies 256~~ \ne ~~185\qquad \leftarrow \textit{nope, it isn't}[/tex]

Answer:

25%

Step-by-step explanation:

So you subtract the number of peak minutes Katie used last month from the number of peak minutes Katie used this month. Divide the difference by the number of peak minutes Katie used last month. Then multiply by 100 to find the percent increase. Katie used 25% more peak minutes this month than last month.

Hope i helped

Answer:

25%

Step-by-step explanation:

Step-by-step explanation:

The diagonals of a square bisect each other, are perpendicular to each other, bisect opposite angles and are congruent.

Answer:

5

Step-by-step explanation:

because it is the right answer

Answer:

8 weeks

Step-by-step explanation:

265-30 = 240

240/30(per week)=8

Answer is 8 weeks