SOLUTION: if the angle of the triangle is 70 , 3y-20 , and y+10 . . . what does y equal

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Question 622846: if the angle of the triangle is 70 , 3y-20 , and y+10 . . . what does y equal

Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
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if the angle of the triangle is 70 , 3y-20 , and y+10 . . . what does y equal
:
We know the 3 angles of a triangle add up to 180
therefore
70 + (3y-20) + (y+10) = 180
Combine like terms
3y + y + 70 - 20 + 10 = 180
:
4y + 60 = 180
:
4y = 180 - 60
:
4y = 120
y = 120%2F4
y = 30
:
:
Check this by finding the other angles and their sum
70 + 3(30)- 20 + (30+10)
70 + 70 + 40 = 180