Checkpoint: Comparing Solving Methods Solution

Checkpoint: Comparing Solving Methods Solution

Solve using the method that is indicated.

Square Root

$x^{2} = d$

$\begin{array}{rcl} \sqrt{x^{2}} & = & \pm \sqrt{d} \\ x & = & \pm \sqrt{d} \end{array}$

Factoring

$\begin{matrix} x^{2} - d = 0 \end{matrix}$

$\begin{matrix} (x + \sqrt{d}) (x - \sqrt{d}) \end{matrix} = 0 x = - \sqrt{d} x = \sqrt{d} x = \pm \sqrt{d}$

Note

Either method is correct when solving a quadratic equation in the form ax2–c $a x^{2} - c$ . Encourage your student to discuss which method they prefer and why.