a right 90 degrees triangle/ label L,J and K. JK is 7 and angle L is 31.6.solve the given right triangle

You know two angles, so the third is 90-31.6 degrees.

now you know three angles, one side.

Let J be the right angle, then K is 58.4deg. It doesn't matter if you let J or K be the right angle.

Draw the triangle. You can solve the triangle with trig functions now.