You can
put this solution on YOUR website!There are (at leastl!) TWO ways to set up this equation. I think the easier way is to:
Let x= one of the angles
2x+21 = the other angle
The equation is
x + 2x +21 = 90
3x +21=90
3x = 69
x=23 degrees
2x+21 = 46+21 = 67 degrees
Check: 23 +67 = 90
The other way is to
Let x = the first angle
90-x = the second angle
The equation is from this sentence, where of course "IS" means "=":
The second angle IS 21 more than twice the first angle.
90-x= 2x+21
It comes out the same.
R^2 at SCC