ANSWER: ∠T = 32.4°
Remember the formula for the basic trig functions: SOH CAH TOA
Since you want to find cosine for <T, you need the adjacent side length as well as the hypotenuse's length which can be found using the Pythagoras's Theorem with <em>a </em> and <em>b</em> being the side lengths and <em>c</em> being the hypotenuse.
Using the theorem, we get c=37
Now use the cosine formula to get <T = 12/37 to get the final answer.