Answer:
x = 3
x = -6
Explanation:
Hello!
Let's first set the equation to 0.
To factor, first think about two numbers that multiply to -18, but add up to 3. The two numbers are 6 and -3.
Now, expand 3x to 6x and -3x. Then, factor by grouping.
Factor
- x² + 3x - 18 = 0
- x² + 6x - 3x - 18 = 0
- (x² + 6x) - (3x + 18) = 0
- x(x + 6) -1(3)(x + 6) = 0
- (x - 3)(x + 6) = 0
Now, set each factor to 0 and solve for x
Solve
- (x - 3) = 0
x = 3 - (x + 6) = 0
x = -6
x = 3, x = -6