The perimeters of the square and the rectangle
below are the same. Write
and solve an equation to find
the value of x.

Step-by-step explanation:

Find the side length of the square. The formula is for area is

So take the square root to find the side length.

Now find the perimeter of the square.

setup the equation to solve for x. The left side is the perimeter of the rectangle and the right is the perimeter of the square.

Collect like terms

subtract 4 from both side

divide both side by 8

second option

step-by-step explanation:

the measures of a triangle equal 180. use that to find x.

2x+3x+4x=180

9x=180

9x/9=180/9

x=20

now you know x, you know angle a is 40°, angle b is 60°, angle c is 80°.

because angle a is 40°, the first option doesn't work.

because angle b is 60°, the second option does work.

when you add angle a and b, you get 100°. complementary means it equals 90°, so the third option doesn't work.

when you add angle a and c, you get 120°, which is not 100.