Answer:
it is 40*
Step-by-step explanation:
because you know 1 and 3 is 20*
so that would make 2 and 4 the same
witch is 40*
∠ 2 = 160°
1 and 2 are adjacent angles and are supplementary, thus
1 + 2 = 180° , that is
20° + 2 = 180° ( subtract 20° from both sides )
A = 160°
