Answer
The student is wrong as the slope is $-\frac{3}{2}$.
The student failed to put the negative sign.
Work Step by Step
Solve for the slope $m$ using the formula $m=\dfrac{y_2-y_1}{x_2-x_1}$ to obtain:
$$m=\dfrac{-4-2}{1-(-3)}=-\dfrac{6}{4}=-\dfrac{3}{2}$$
The student failed to indicate or write the negative sign..