2/3 ÷ 8/9 with explanation and steps... ​

Answer:

x = π/4 and 5π/4

Step-by-step explanation:

Given the expression;

2cos²x - 1 = 0

2cos²x = 0+1

2cos²x = 1

cos²x = 1/2

cos x = ±√1/2

cos x = ±0.7071

x = arccos(±0.7071)

x = ±45 degrees

Convert to radians

Sence 180° = π rad

45°  = x

x = 45π/180

x = π/4

If x = -45°

Since cos is negative in the 3rd quadrant

x = 180 + 45

x = 225°

x = 225π/180

x = 45π/36

x = 5π/4

Answer:

When a point is reflected across the y axis the values of x change. They become negative values of x.

Answer:

(B) The x-coordinate changes.

Step-by-step explanation:

Step-by-step explanation:

here is the answer. Hope that helps.

Answer:

14.8f + 1.8g + 12.1d

Step-by-step explanation:

combine like terms.

3.6+8.5= 12.1

6.2+8.6= 14.8

-2.7+4.5= 1.8

Answer:

acute angle and number 3 is obtuse

Step-by-step explanation:

Sohail=17

afzal=16

Bilal=12

Aslam=16+5=21

Answer:

So I did my work so many times and I got 9 but I don't know Imaooo sry :)

Step-by-step explanation:

Step-by-step explanation:

this is the hardest I think

Answer:

Option A

Step-by-step explanation:

If the speed of a car in miles per hour (m) is proportional to the speed in kilometers per hour (k),

m ∝ k

m = ck

Here, c = Proportionality constant

Therefore, c = [tex]\frac{m}{k}[/tex] should be constant for each value given in the table.

For m = 11 and k = 17.699,

c = [tex]\frac{11}{17.699}[/tex]

c = 0.6215

For m = 26 and k = 41.834,

c = [tex]\frac{26}{41.834}[/tex]

c = 0.6215

For m = 34 and k = 54.706,

c = [tex]\frac{34}{54.706}[/tex]

c = 0.6215

Therefore, c is constant for each value of m and k.

Option A will be the correct option.

B

Step-by-step explanation:

If you're using a Casio calculator you can just change the mode to table mode. Put the equations as they are,decide the value of the X axis you want to start at and where you want to end. The step you can use 1 if you want. Press = button. You'll have the co-ordinates. Plot the co-ordinates of each equation and see which one gives a straight line graph. I started at -4 and ended at 5 and I used step 1

Answer:

The median is 9

Step-by-step explanation:

The median is the number in the middle. The middle of this is 8 and 10, so you plus them and divide by to 2, then it gives 9, so the median is 9.

Answer:

Option 3 is correct

tex]\frac{1yd}{36 in}=\frac{7yd}{252 in}[/tex]

Step-by-step explanation:

1.[tex]\frac{1 in}{2.54 cm}=\frac{7 in}{17.68 cm}[/tex]

1 in=2.54 cm

[tex]7 in=2.54\times 7=17.78 cm[/tex]

[tex]\frac{1 in}{2.54 cm}=\frac{1 in}{1 in}=1[/tex]

[tex]\frac{1 in}{2.54 cm}\neq \frac{7 in}{17.68 cm}[/tex]

Hence, it is not correct.

2.[tex]\frac{1 ft}{12 in}=\frac{7ft}{74 in}[/tex]

1 foot=1 2in

[tex] 7ft=7\times 12=84 foot[/tex]

[tex]\frac{1 ft}{12 in}=1[/tex]

[tex]\frac{7ft}{74 in}\neq 1[/tex]

[tex]\implies \frac{1 ft}{12 in}\neq \frac{7ft}{74 in}[/tex]

Hence, it is not correct.

3.[tex]\frac{1yd}{36 in}=\frac{7yd}{252 in}[/tex]

1 yd=36 in

[tex]\frac{1yd}{36 in}=\frac{36}{36}=1[/tex]

[tex]7yd=7\times 36=252 in[/tex]

[tex]\frac{7yd}{252 in}=\frac{252 in}{252 in}=1[/tex]

[tex]\implies \frac{1yd}{36 in}=\frac{7yd}{252 in}[/tex]

Hence, it is correct.

4.[tex]\frac{1 m}{3.28ft}=\frac{7m}{22.86ft}[/tex]

1 m=3.28 ft

[tex]\frac{1 m}{3.28ft}=\frac{3.28}{3.28}=1[/tex]

[tex]7m=7\times 3.28=22.96 ft[/tex]

[tex]\frac{7m}{22.86ft}\neq 1[/tex]

[tex]\frac{1 m}{3.28ft}\neq \frac{7m}{22.86ft}[/tex]

Hence, option is not correct.

Answer:

7 m

Step-by-step explanation:

A = base x height

56 = 8 x h

56/8 = h

h = 7

Answer:

The trainers are 44.71% off the original price i think.

Step-by-step explanation:

pls mark me as brainlist

thanks a lot

Answer:

Father=41

Son=19

Step-by-step explanation:

Father=f

Son=s

f+s=60

Eight years ago would mean that 16 is subtracted from 60 since there is both of them

3s+s=4s

4s=44

s=11

11+8=19

33+8=41

Answer:

Multiplication property of the equality

Answer:

24) x = 9.2

25) x = 30.8

Step-by-step explanation:

Given

See attachment for triangles

Solving (24)

To solve for x, we make use of cosine formula

i.e.

cos(40) = adjacent ÷ hypotenuse

So, we have:

cos(40) = x ÷ 12

Multiply both sides by 12

12 cos(40) = x

12 * 0.7660 = x

x = 9.2

Solving (25)

To solve for x, we make use of sine formula

i.e.

sin(25) = opposite ÷ hypotenuse

So, we have:

sin(25) = 13 ÷ x

Multiply both sides by

x sin(25) = 13

Divide by sin(25)

x = 13 ÷ sin(25)

Using a calculator

x = 30.8

Answer:

(B n C) = {b,c}

A = {a,b,c}

B= {b,c,d}

C= {b,c,e}

A u (B n C) = {a,b,c}

(A u B) = {a,b,c,d}

(A u B) n C = {b,c}

(A u C) = {a,b,c,e}

(A u B) n (A u C) = {a,b,c}

Answer:.

Step-by-step explanation:

(r,θ) = (7.28,254.05°) are 2-7i in polar coordinates on the complex plane.

The polar coordinates system is a two-dimensional coordinate system in which each point is determined by distance from the point and an angle from the reference direction.

I. Polar form = (r,θ) = (7.28,254.05°)

z = 2 - i7

r= [tex]\sqrt{ 2^2+-7^2}[/tex]

= √53

 = 7.28

θ = tan^-1 (-7/-2)

  =3.5

  = 74.05

Point lies in the third quadrant

Hence θ = 180+74.05

              = 254.05°

Polar form = (r,θ) = (7.28,254.05°)

II. Z=16

De Moivre's theorem states if

z= r(cos(θ) + i sin (θ)) , then

[tex]z^2=r^2(cos(n\theta)+ i sin (n\theta))[/tex]

[tex]r= \sqrt{1^2+1^2}[/tex]

= √2

θ= arc tan (1/1)

  = π / 4

z= √2 (cos (π / 4)+i sin (π / 4))

z^8 = (√2 (cos (π / 4)+i sin (π / 4)))^8

= (√2 (cos (8π / 4)+i sin (8π / 4)))^8

=16 (cos(2π) + i sin (2π)

=16

Learn more about polar form;

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Answer:

Slope of the line perpendicular to the given line = [tex]- \frac{1}{4}[/tex]

Step-by-step explanation:

If two are lines are perpendicular to each other,

the product of their slopes = - 1 .

That is ,

      [tex]m_ 1 \times m_2 = -1[/tex]

Slope of the given line :

[tex]m_ 1 = 4[/tex]

Hence slope of the line perpendicular to it :

                                                                [tex]4 \times m_ 2 = - 1 \\\\\frac{4}{4} \times m_2 = - \frac{1}{4} \\\\1 \times m_2 = - \frac{1}{4}\\\\m_ 2 = \frac{-1}{4}[/tex]

The slope of the line perpendicular to the equation y = 4x + 9 is m = -1/4

What is an Equation of a line?

The equation of a line is expressed as y = mx + b where m is the slope and b is the y-intercept

And y - y₁ = m ( x - x₁ )

y = y-coordinate of second point

y₁ = y-coordinate of point one

m = slope

x = x-coordinate of second point

x₁ = x-coordinate of point one

The slope m = ( y₂ - y₁ ) / ( x₂ - x₁ )

Given data ,

Let the equation of line be represented as A

Now , the value of A is

y = 4x + 9   be equation (1)

The equation is of the form y = mx + b where m is the slope and b is the y-intercept

Substituting the values in the equation , we get

Slope m = 4

Now , the second line is perpendicular to the line A , the product of slopes of the lines will be -1

So , m₁ x m₂ = -1

4 x m₂ = -1

Divide by 4 on both sides of the equation , we get

m₂ = -1/4

Therefore the value of m₂ is -1/4

Hence , the slope of the line is m₂ = -1/4

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Answer:

Hexagon AGHBGHCGHDGHEGHFGH coincides with hexagon ABCDEF when GH passes through the midpoints of opposite sides; that is, it is a perpendicular bisector of the two sides. HexagonAGHBGHCGHDGHEGHFGH also coincides with hexagon ABCDEF when the line of reflection joins a pair of vertices opposite one another on the hexagon. There are three perpendicular bisectors and three pairs of opposite vertices. In all, there are six lines of reflection that will map the hexagon back onto itself.

Step-by-step explanation:

Answer:

Step-by-step explanation:

Six liters of paint will cover 50 square meters.

  6L ⇒ 50m²

then,

  1L ⇒ 50/6 m²

  9L ⇒ 50 × [tex]\frac{9}{6}[/tex] m²

       ⇒ 75 m²

answer:

-4

Step-by-step explanation:

-3x>12

x<-4

the correct graph is graph b

Answer:

y = -5

o = 35 degrees

Step-by-step explanation:

If you replace y with -5, the statement  7y = 4y - 15 is correct. You get -35 =  -35. Hope this helped!

Answer:

a = 15

34.8 + b = 54.6

Step-by-step explanation:

First one:

5a - 10b = 45  (b = 3)

5a - 10(3) = 45

5a - 30 = 45

5a = 75

a = 15

Second one

b + a + 3a = 54.6

b + 4a = 54.6   ( a = 8.7)

b + 4(8.7) = 54.6

b + 34.8 = 54.6

34.8 + b = 54.6

Answer:

a=15 26.1 + b =54.6

Step-by-step explanation:

for the second question we first multiply 8.7 by 3 which gives us 26.1 and since there is only one answer with 26.1 it's it.

Answer:

you are posting unvisibile photo pls fix it

Step-by-step explanation:

9514 1404 393

Answer:

  20.0 square units

Step-by-step explanation:

There are many ways the area can be computed here. Perhaps the intended one is to find the length of the third side, then use the usual triangle area formula.

  b = √(c² -a²) = √(9² -7²) = √32 ≈ 5.7

Then the area is ...

  A = 1/2bh = 1/2(5.7)(7) ≈ 20.0

The area is approximately 20.0 square units.

_____

Additional comment

It is highly unusual to make use of rounded intermediate results. That is a guarantee that the final answer will have more error than necessary. Ordinarily, you would never do that.

An alternate solution might be ...

  angle = arccos(7/9) ≈ 38.9°

  area = 1/2(7)(9)sin(38.9°) ≈ 19.8 . . . . square units (assuming the sine value is not rounded to 0.6)