Question

Two lines intersect at a point, forming ​ ∠1 , ∠2 , ∠3 , and​ ​ ∠4 ​ . ∠1 and ∠3 are vertical angles. ∠2 and​ ​ ∠4 are vertical angles. m∠1=70° What is the measure of ​​ ∠2 ​?
20°
70°
90°
110°

Answer 1

angle 1 and angle 2 are a linear pair, which make a sum of 180
angle 2=180-angle 1=180-70=110

Answer 2

< 1 + < 2 = 180.....because they form a linear pair and equal 180
70 + < 2 = 180
< 2 = 180 - 70
< 2 = 110 <==