Question

d) In a triangle ABC, (angle A + angle B) = 100° and (angle B + angle C) = 120°, find the value of angle A and angle C.




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Answer 1

Answer:

angle A =60°

angle C =80°

Step-by-step explanation:

In ∆ABC

angle A + angle B +angle C= 180° (sum of the angles of a triangle is 180°)

100° + angle C =180° (since angle A+ angle B= 100°)

angle C = 180°-100° =80°

In ∆ABC

angle A + angle B + angle C =180°

angle A + 120° = 180°(since angle B+ angle C =120°)

angle A=180°-120°=60°

Answer 2

Answer:

Angle a=60

angle c=80

Step-by-step explanation:

a+b=100

b+c=120

property of exterior angles

exterior angle c=100

angle c is 100-80=80

angle b is 120-80=40 because b+c=120

angle a is 100-40=60 because a+b=100