What is the value of X?

Question

Jane’s pool is in the shape of the trapezoid with the dimensions x + 20, x + 70, 2x, and x + 70. If the perimeter of the pool is 3240, what is the value of X?

Please help, I’ve been struggling with this question for a while.

Answer 1

The perimeter of the trapezoid would be the four sizes added together:

3240 = x + 20 + x + 70 + 2x + x + 70

The first thing that needs to be done is combining like terms:

3240 = 5x + 20 + 70 + 70

3240 = 5x + 160

 

Looks a lot less daunting now, doesn't it?

Now we subtract 160 from both sides:

3080 = 5x

All you have to do now is divide both sides by 5, and you'll have you x-value.