all angles are 180 degrees

Question

in a triangle the sum of all angles is 180. in ABC, angle b is 20 less than angle A and angle C is 10 more than three times angle A

Answer 1

a + b + c = 180

b = a - 20

c = 3a + 10

 

a + (a-20) + (3a+10) = 180

5a - 10 = 180

5a = 190

a = 38

 

b = a - 20 = 18

 

c = 3a + 10 = 3(38)+10 = 124