SOLUTION: I am trying to find the measure for the angles of a triangle. One angle is twice the measure of a 2nd angle, & the 3rd angle is three times the 2nd angle decreased by 12. The answe

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Question 258252: I am trying to find the measure for the angles of a triangle. One angle is twice the measure of a 2nd angle, & the 3rd angle is three times the 2nd angle decreased by 12. The answer is in the back of the book. But I want to know how to get there from here.
Found 2 solutions by richwmiller, ankor@dixie-net.com:
Answer by richwmiller(17219)   (Show Source): You can put this solution on YOUR website!
a=2b
c=3b-12
a+b+c=180
a = 64, b = 32, c = 84

Answer by ankor@dixie-net.com(22740)   (Show Source): You can put this solution on YOUR website!
One angle is twice the measure of a 2nd angle, & the 3rd angle is three times the 2nd angle decreased by 12.
:
Reading it we can see it would be good to get the 1st and 3rd angles in terms of the 2nd angle
:
Let x = the 2nd angle
:
It says,"One angle is twice the measure of a 2nd angle", therefore
"one angle" = 2x
and
"the 3rd angle is three times the 2nd angle decreased by 12.", therefore:
3rd angle = 3x - 12
;
It's a triangle so we can say:
2x + x + (3x-12) = 180
6x = 180 + 12
6x = 192
x =
x = 32 degrees is the 2nd angle
then
2(32) = 64 degrees is the one angle
and
3(32) - 12 = 84 degrees is the 3rd angle
;
:
confirm this: 64 + 32 = 84 = 180
:
did this light way for you on this problem?

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