Question 161851
a+b+c=180


"angle a is 4 times greater than angle b" __ a=4b


"angle c is 20 degrees less than angle b" __ c=b-20


substituting __ (4b)+b+(b-20)=180 __ 6b=200 __ b=100/3


substituting __ a=4(100/3) __ a=400/3


substituting __ c=(100/3)-20 __ c=40/3