Question

Find the values of the unknown angles marked with letters. please help me- it is about alternate angles

100 points!!!
a ?
b ?
c ?
d ?

Answer 1

Explanation:

Find either c or d first. Those are easy and everything will fall into place after those 2 are found.

c: angle c is supplementary with 115. That means that they add up to equal 180; therefore, 115° + c° = 180° so c = 65°.

d: angle d is supplementary with 70. Therefore, 70° + d° = 180° so d = 110°.

a and c are same side interior, so they are also supplementary. That means that a = 115°.

b and d are also same side interior, so they are also supplementary. That means that b = 70°.