Question

I need help with this

Answer 1

Answer:

3 cm

Step-by-step explanation:

The shaded area is the total area of the rectangle less the area of the unshaded square. The area of the rectangle is the product of its length and width:

A = (5x)·(3x) = 15x^2

Likewise, the area of the square is the product of its length and width:

a = (x)·(x) = x^2

Then the shaded area is the difference:

126 cm^2 = A -a = 15x^2 -x^2 = 14x^2

Dividing by 14 gives ...

9 cm^2 = x^2

and taking the square root tells us the value of x:

3 cm = x

This answers the question:

The side length of the square, x, is 3 cm.