Question

if the measure of m∠2 is equal to 45°, what is the measure of m∠3?
question 4
if the measure of m∠2 is 40°, what is the measure of m∠7?

Explanation:

Step1: Identify angle - pair relationship

$\angle2$ and $\angle3$ are corresponding angles. If the lines $l$ and $m$ are parallel, corresponding angles are equal.
Since $\angle2 = 45^{\circ}$, then $\angle3=45^{\circ}$.

Step2: For the second part about $\angle2$ and $\angle7$

$\angle2$ and $\angle7$ are vertical - angles. Vertical angles are equal. Given $\angle2 = 40^{\circ}$, then $\angle7 = 40^{\circ}$.

Answer:

The measure of $\angle3$ is $45^{\circ}$ and the measure of $\angle7$ is $40^{\circ}$.