Find the Perfect Square Trinomial r^2+4r

$r^{2} + 4 r$

Step 1

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

Divide $4$ by $2$ .

$2^{2}$

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

$4$

Step 2

Add $4$ to get the perfect square trinomial.

$r^{2} + 4 r + 4$