What theorem do we use to solve for a side of a right triangle?

I would believe you are talking about the Pythagorean Theorem:

In that case the formula is L^2 + L^2 = H^2.

If you have the hypotenuse it is:

H^2 - L^2 = L^2:

When solving, just substitute your lengths for each side of the triangle.

Note: This only works with right triangles.

34.5 cm

step-by-step explanation:

generally for a circular segment of angle, θ° and radius r

arc length

= (θ/360) x circumference

= (θ/360) x 2πr

in our case, θ = 60°, π=3.142 and r = 33 cm

substitute into above formula

arc length

= (60/360) x 2(3.142)( 33) = 34.5 cm