What is measure of angle r?

enter your answer as a decimal in the box. round only your final answer to the nearest hundredth.

You have three options, all of them work.
sin(angle) = opposite/hypotenuse
cos(angle) = adjacent/hypotenuse
tan(angle) = opposite/adjacent

You are already given the length of the lines, so all you can is to take the inverse of whatever you choose to get the angle.

(5/13) = 22.62

(12/13) = 22.62

(5/12) = 22.62