Answer:
140
Step-by-step explanation:
Angles 1 and 3 are corresponding angles.
Assuming the lines the transversal goes through are parallel, they are congruent.
With that assumption we have the following equation to solve for x:
20x+60=30x+20
Divide both sides by 10:
2x+6=3x+2
Subtract 2x on both sides:
6=(3x-2x)+2
Simplify:
6=(1x)+2
Simplify:
6=x+2
Subtract 2 on both sides:
6-2=x
Simplify
4=x
So the measure of angle 1 is
20x+60 evaluated at x=4:
20(4)+60
80+60
140
