Question

if a,b are complementary angles and b,c are supplementary angles If the average of a abd c is 85, then find a+b+c

Answer 1

Answer:

220°

Step-by-step explanation:

ATQ,

a + b = 90° (1)

b + c = 180° (2)

(1) + (2)

=> (a + b) + (b + c) = 90° + 180°

=> a + 2b + c = 270°

=> a + c = 270° - 2b

Dividing both sides by 2 -

=> (a+c)/2 = (270°-2b)/2

=> 85 = 135° - b

[As it is was given that average of a and c is 85]

=> b = 135 - 85 = 50°

So in (1)

a = 90° - 50° = 40°

and in (2)

c = 180° - 50° = 130°

Hence a + b + c = 50° + 40° + 130° = 220°