the dimensions of a door are 3ft by 7ft 6in. if the same amount is added to each dimension of the door, the area is increased by 18ft^2. Find the dimensions of the new door.

2 answers

(3+x)(7.5+x) = 3*7.5+18
x = 3/2

new dimensions: 4'6" by 9'0"

check:
3*7.5 = 22.5
4.5*9 = 40.5
How did you get 3/2 or 1.5