x=20 degrees
First we can recall that, supplementary angles sum up to 180. So, we can think of an equation…
(2x+15) + (6x+5)=180
Combine like terms,
(8x+20)=180
Subtract 20 degrees from both sides
8x=180
Divide by 8
x=20
If you plug 20 into both expressions and add them up, you will see that it checks out…
I hope this helped