Question 965345
supplementary angles add up to 180 degrees
so we know a + b = 180
a is four times as large as b
so a = 4b
substitute 4b for a into a + b = 180
4b + b =180
combine like terms
5b = 180
divide both sides by 5 to get the variable b by itself
b = 36
plug 36 back into the original equation to figure out what a is
a + 36 = 180
subtract 36 from both sides
a = 144

answer angle a is 144 degrees and angle b is 36 degrees