Question

Consider the figure below, where line a is parallel to line b:

Angle 4 = 12m - 4
Angle 5 = 10m + 20
Calculate the measure of Angle 5.

Answer 1

Angle 5= 140

Explanation:

I assume you are talking about parrallel lines and a transversal. If that is the case, I can guess that angles 4 and 5 are alternate exterior angles. Therefore they are congruent.

1. 12m-4=10m+20
2. 12m=10m+24 You add 4 to -4 and 20
3. 2m=24 You subtract 10m from 10m and 12m
4. m=12 Divide both sides by 2
5. 10(12)+20 Substitute m for 12 in the equation for Angle 5
6. 120+20 Multiply 10 by 12
7. 140 Add 120 and 20