We have a rectangle of dimensions x - 2 by 2x + 5 such that its area is 8x-6 . What is the value of x?
+130071 Area of rectangle = product of the dimensions
(x - 2) (2x + 5) = 8x - 6 simplify
2x^2 - 4x + 5x -10 = 8x - 6 rearrange as
2x^2 + x -10 = 8x - 6
2x^2 - 7x - 4 = 0 factor as
(2x + 1) ( x - 4) = 0
We need a positive value for x .....the second factor set to 0 will give us that
x - 4 = 0
x = 4
