Question

Angle A and angle B form a liner pair , if angle A=5a+16 degree and angle B =a+104 degree .find 'a' and the measure of angle A

Answer 1

since angle A and angle B forms a linear pair, then

angle A + angle B=180°,

5a+16° + a+104° =180°

6a+120°=180°,

then

6a=180°-120°,

6a=60°,

then

a=10°,

therefore

angle A=5×10°+16°,

angle A=50°+16°=66°

Answer 2

given angle A = 5a + 16

and angle B = a + 104

sum of linear angles = 180°

A + B = 180

5a + 16 + a + 104 = 180

6a = 180 - 120

6a = 60

a = 10

so angle A = 5a + 16 = 5× 10 + 16 = 66°

angle B = a + 104 = 10 + 104 = 114°

hence , a = 10 , and the measure of angle A = 66°