Hello, biker.josh07!

I have a "visual" solution.

Show that if:

then this is equivalent to the expression:

Since , then two angles are.complementary

Consider this right triangle:

Code:* * | * x | * | * | a * | * | * 2y | * - - - - - - - * b

. . and are in the same right triangle.

Hence: .

Therefore: .