Answer:
See below for answers
Explanation:
Part 1:
Angle 1 is a supplementary angle, so it must be 180-50=130 degrees because supplementary angles add up to 180 degrees.
Angle 2 is a vertical angle, therefore it must be 50 degrees as well because vertical angles are congruent.
Angle 3 is vertical to angle 1, so it is 130 degrees since vertical angles are congruent.
Part 2:
x and 2x+21 are supplementary angles, so we can make an equation:
x+2x+21=180
3x+21=180
3x=159
x=53
So x=53