Angle help: The second angle of a triangle is 15 degrees les

stahl7639

New member
Joined
Sep 15, 2006
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3
The second angle of a triangle is 15 degrees less than twice the first. The third angle is the sum of the other two angles. Find the measure of the angles.

I am stuck with my formula

b=2a-15
c=a+b
a+b+c=180

I just can't figure outhow to arrive at an answer.
 

galactus

Super Moderator
Staff member
Joined
Sep 28, 2005
Messages
7,216
Let x=the first angle

the second angle will be 2x-15

the third angle is x+2x-15

Therefore, since they must sum to 180:

Solve: x+2x-15+x+2x-15=180

6x-30=180

Find x and, thus, the other angles.
 
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