Question

Find the measure of each lettered angle. a=, b=, c=, d=, e=

Answer 1

a = 20°

b = 70°

c = 20°

d = 70°

e = 110°

Explanation:

Angle A is complementary with 70°, so they add together to = 90° (as indicated by the 90° mark).

90° - 70° = 20°

Angle A = 20°

Angle B is complementary with angle A, 20°, so they also add together to = 90°.

90° - 20 = 70°

Angle B = 70°

Although not indicated by a 90° mark, Angle C and Angle B are complementary since they share a straight line with the complementary angles A and 70°. This means Angles C + B = 90°

90° - 70° = 20°

Angle C = 20°

Angle D is vertical to 70°, so Angle D = 70°

Angle E is supplementary to 70°, so they should combine to = 180°

180° - 70° = 110°

Angle E = 110°

Answer 2

a= 20

b= 70

c= 20

d=70

e=110

Explanation:

a + the 70 degree angle have to equal 90 degrees (the right angle marking) and the same with b + a. So to ind a, you do 90-70 and to find b, because you now have the value of a, you do 90-20.

a+b+c+70 is equal to a 180 degree angle, so since you know the value of a and b, now you can figure out c by doing 180-(70+20+70).

d and the 70 degree angle are vertical angles so they are equal to each other.

lastly for e, d+e is equal to 180 degrees so since you know the value of d, you just do 180-70 to find e.