Since there is a box at the corner of the angle, that means that angle is 90°. So, we can add the 2 values given to us and set them equal to 90°.
39+4q-5=90
Now we can combine the 2 like terms on the left side of the equation.
34+4q=90
Now we subtract the 34 from 90
4q=56
Now to get q by itself (find the value of q) we divide the 4 from both sides and we get our answer.
Answer: q=14
Hope this helps :)
