Question

Cet. Factor and Solve. x^2 + 3x - 18 = 0 - Ready? Enter your answer

Answer 1

Answer:

x = 3  or  x = - 6

Step-by-step explanation:

Factor and Solve. x^2 + 3x - 18 = 0

We can use the Diamond method of factoring.

Factor -18 = 6 * -3;    and  3 = 6 + -3

so

x^2 + 3x - 18 = x^2 -3x + 6x - 18  = 0

= (x^2 -3x)   +  ( 6x - 18)  = 0

= (x^2 -3x)   +  ( 6x - 18)  = 0

= x(x - 3)  + 6*(x - 3) =0

= (x - 3)*(x + 6) = 0

so  Either  x - 3 = 0   or   x + 6 = 0

x = 3  or  x = - 6