Question

The first step for deriving the quadratic formula from the quadratic equation, 0 = ax2 + bx + c, is shown.

Step 1: –c = ax2 + bx

Which best explains or justifies Step 1?

subtraction property of equality
completing the square
factoring out the constant
zero property of multiplication

Answer 1

Completing the square.

Explanation:

ax2 + bx + c has "x" in it twice, which is hard to solve.

But there is a way to rearrange it so that "x" only appears once. It is called Completing the Square