L = 4 w + 3
A = L w = [ 4 (5x-7) + 3 ] (5x-7)
= [ 20 x - 28 + 3 ] (5x-7)
= (20x - 25)(5x+7)
= 5 (4x-5)(5x+7)
= 5 (20 x^2 +3 x -35)
= 100 x^2 + 15 x - 175
The width of a rectangle is (5x-7). Find the polynomial equation reppresenting the area of the rectangle if its lenght is three more than four times as long as its width
1 answer