How do you solve this

Answer:
8. 105 degrees
9. 75 degrees
10. 105 degrees
Step-by-step explanation:
The given angle is 75 degrees. The four angles together make up 360 degrees because quadrilaterals have a measurement of 360 degrees on the inside. The angle that is 75 degrees and angle 2 are opposites (I forgot the math word, sorry) so they are the same degrees. So we know that angle 2 is 75 degrees. Angles 1 and 2 are vertical pairs, as well as the given angle and angle 3. We know that vertical pairs equal 180 degrees. 180 - 75 = 105 degrees. Now we know that both angle 1 and 3 are 105 degrees. You could also find the measurment of angle 1 and 3 by making an equation.
Given angle + Angle 2 + Angle 1 + Angle 3 = 360 degrees
(75 + 75 + 2x = 360)
150 + 2x = 360
2x = 210
x = 105