Answer:
[tex]x = 3, x = -12[/tex]
Step-by-step explanation:
Hello!
We can factor the quadratic by grouping. We have to find two numbers that add up to 9 but multiply to -36.
The two numbers are 12 and -3. Expand 9x to 12 x and -3x.
Factor by Grouping
- [tex]x^2 + 9x - 36 = 0[/tex]
- [tex]x^2 +12x - 3x -36 = 0[/tex]
- [tex]x(x + 12) - 3(x + 12) = 0[/tex]
- [tex](x - 3)(x + 12) = 0[/tex]
- [tex]x = 3, x = -12[/tex]
The answer is Option B. x = 3 or -12.
