Every triangle measures 180 degrees.
In order to get the answer you need to add every equation and set it equal to 180.
2x+4+2x-9+x=180
Combine like terms.
5x-5=180
Add 5 to the other side.
5x=185
Divide by 5.
x = 37
Now, plug 37 in for every x.
Angle A: 2(37)-9
Angle B: 2(37)+4
Angle C: 37
The measures are:
Angle A = 65
Angle B = 78
Angle C = 37
Hope this helps!
