Question 176480
let a and b be our supplementary angles
:

b=4a-30..........eq 1
a+b=180..........eq 2
:
rewrite eq 2 to b=180-a and plug it into eq 1
:
180-a=4a-30
:
5a=210
:
{{{highlight(a=42)}}}degrees
:
{{{highlight(b=4(42)-30=138)}}}degrees