Question

x^2+9x−36=0
solve the quadratic equation

Answer 1

Let's first see if we can solve this quadratic equation by factoring.

After listing the factors of -36, are there any that will add to 9? After some guessing and checking, you can realize that 12 and -3 will multiply to -36 and add to 9.

Thus, we can simplify our quadratic equation as follows:

$x^2 + 9x - 36 = 0$

• Set up

$(x + 12)(x - 3) = 0$

• Factor

$x + 12 = 0 \,\,\,\, \textrm{and} \,\,\,\,x - 3 = 0$

• Apply the Zero Product Property

$x = 3, -12$

• Solve both equations