You can
put this solution on YOUR website!Let's call the angles A,B, and C.
.
.
.
"one angle of a triangle is 20 degrees more than the measure of the second angle"
1.

"The measure of the third angle is 30 degrees more than twice the sum of the measures of the first two angles."
2.

Also, since it's a triangle you know that,
3.

Use eq. 1 and 2 and substitute in eq.3,
3.

from eq.1,

from eq. 2,
You can
put this solution on YOUR website!A=B+20
C=2(A+B)+30
A+B+C=180
(B+20)+B+2(A+B)+30=180
B+20+B+2(B+20+B)+30=180
B+20+B+2B+40+2B+30=180
6B=180-20-40-30
6B=90
B=90/6
B=15 DEGREES FOR THE MIDDLE ANGLE.
A=15+20=35 FOR THE FIRST ANGLE.
C=2(15+35)+30=2*50+30=100+30=130 FOR THE THIRD ANGLE.
15+35+130=180
180=180
You can
put this solution on YOUR website!Lets call the 1st angle A. Angle 2 which we will call B is 20 more than the 1st angle so A+20=B and the 3rd angle which we will call C is twice the sum of the the first 2 angles(A and B)plus 30 degrees so 2(A+B)+ 30=C....Lets solve for C in terms of A in this equation: 2A+2(A+20)=C simplifying C=4A+70. Now, we know that A+B+C=180. So lets plug in our values A+(A+20)+(4A+70)=180 solving for A we get A=15 Degrees since B=A+20 B=35 Degrees and C=4A+70 so C=130 degrees.