Answer
$$3\left(r+\frac{3}{2}\right)^2-\frac{43}{4}$$
Work Step by Step
Completing the square, we obtain:
$$3\left(r^2+3r-\frac{4}{3}+\left(\frac{3}{2}\right)^2-\left(\frac{3}{2}\right)^2\right) \\ 3\left(\left(r+\frac{3}{2}\right)^2-\frac{4}{3}-\left(\frac{3}{2}\right)^2\right) \\ 3\left(r+\frac{3}{2}\right)^2-\frac{43}{4}$$
