Question

Solve 5x2 = –45x.

Answer 1

5x^2 = -45x
5x=-45
x=-9

Answer 2

First add 45x to both sides.

\(\Large \color{Black}{\Rightarrow 5x^2 + 45x = 0 }\)

Factor.

\(\Large \color{Black}{\Rightarrow 5x(x + 9) = 0 }\)

Either x is 0, or it is -9.
Correct solution set is (0,-9)