Hi, I can't tell if there's a little square drawn in red to indicate that there's a right angle in the middle. There's some squiggly lines and so it's kind of hard to tell.
I am going to assume that there is. Let me know if there isn't.
The sum of these 3 angles would be 180 degrees.
As an equation, 57 + 90 + x = 180
Solve for x.
147 + x = 180
x = 33 degrees.
So this would be correct ASSUMING that there's a little red square drawn indicating that there's a right angle.