Find the Perfect Square Trinomial r^2-8r

$r^{2} - 8 r$

Step 1

To find the $c$ value $c = {(\frac{b}{2})}^{2}$ , divide the coefficient of $r$ by $2$ and square the result.

Divide $8$ by $2$ .

${(- 1 \cdot 4)}^{2}$

Multiply $- 1$ by $4$ .

${(- 4)}^{2}$

Raise $- 4$ to the power of $2$ .

$16$

Step 2

Add $16$ to get the perfect square trinomial.

$r^{2} - 8 r + 16$