A rectangle has a perimeter of 12y squared - 2y + 18 and has a width of 4y squared - y + 6. What is the length of the rectangle?

Question

I was wondering if the length would already have been doubled for me or if I have to do it. 

Answer 1

P = 2(l + w)

P/2 = l + w

12y² - 2y + 18 = 2(l + 4y² - y + 6)

6y² - y + 9 = l + 4y² - y + 6

l = 2y² + 3

 

 

Answer 2

1) Divide the perimeter by 2.

2) From the quotient subtract the width

3) Write down the length.