Question

Solve x2 + 7x + 12 = 0 for x​

Answer 1

x^2 + 7x + 12 = 0

We know that 4 times 3 is 12.

We also know that 4 plus 3 is 7.

This is all we need to know to create our two factors.

(x + 3) (x + 4) = 0

Set each factor to 0 and solve for x.

x + 3 = 0

x = - 3

x + 4 = 0

x = -4

Answer: x = - 3, x = - 4

Answer 2

-4/3

Explanation:

Isolate x.

x2 + 7x + 12 = 0

2x + 7x + 12 = 0

9x + 12 = 0

9x = -12

x = -12/9

x = -4/3