## Thinking Mathematically (6th Edition)

The equation 5$x^{2}$ + x = 18 can be written in the form a$x^{2}$ + bx + c = 0 by subtracting 18 on both sides. 5$x^{2}$ + x = 18 5$x^{2}$ + x -18= 18 - 18 5$x^{2}$ + x - 18 = 0