SOLUTION: one angle of a triangle is 20 degrees. the second angles measurement is four times the third. what is the measure of the third angle?

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Question 127973: one angle of a triangle is 20 degrees. the second angles measurement is four times the third. what is the measure of the third angle?
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!
one angle highlight%28x=20%29 degrees
the second y=4z
the third z

the sum of all angles in a triangle is 180 degrees, so we will have:
x%2By%2Bz+=180.........substitute x and y
20%2B4z%2Bz+=180.........
5z+=180-20.........
5z+=160.........
z+=160%2F5.........

highlight%28z+=+32%29.........the third angle

y=4z
y=4%2A32
highlight%28y+=+128%29....the second angle
check:
20%2B128%2B32+=180.........
148%2B32+=180.........
180+=+180.........