Find the dimensions of the rectangle below.

Question

Length of x+7, a width of 2x. Area of 520 in².

Answer 1

length x width = area

 

(x+7)(2x) = 520

 

2x² + 14x - 520 = 0

 

x² + 7x - 260 = 0

 

(x+20)(x-13) = 0

 

x = -20 (which is impossible because it creates a negative value for length and width) and x= 13

 

length = 20, width = 14