The right angle is 90 degrees.
The 3 inside angles are a total of 180 degrees.
The two acute angles would need to equal 180-90 = 90 degrees.
Using the ratio you have 3x + 7x = 90
Simplify to get 10x = 90
Divide both sides by 10 to get x = 9
Now you have the two angles:
Angle 1 = 3 x 9 = 27
Angle 2 = 7 x 9 = 63