Okay, so you know by looking at the angle that it is a right angle. Now, recall that right angles have a measurement of 90°. Next, write an equation.  4x + 2x = 90° Simplify. 4x + 2x = 90 6x = 90  x = 15.  Now, to solve for the measurements of both angles, substitute the now known value of x into both equations, and solve. 4(15) = 60 2(15) = 30 Answer: x = 15. The first angle would be 60°, and the second angle is 30°. They both add up to 90°.