### Home > CCA2 > Chapter 4 > Lesson 4.2.1 > Problem4-70

4-70.

Using the technique of completing the square, solve $x^2+12x+15=75\ \text{for}\ x$. Homework Help ✎

See the Math Notes box in Lesson 2.1.4 for help with completing the square. Also see problem 3-117.

$(x+6)^2=96$

What steps were used to obtain this equation?

Now solve the equation.

Take the square root of both sides.

Subtract $6$ from both sides.

Since the original equation had an $x^2$-term, you should try to find 2 solutions.