6 7/12 - 5 2/3 I need help on this Math Promblem

1) in triangle the, what is the measure of angle t (in degrees)? 2) in triangle bat, the measure of angle b is 66∘, and the measure of angle t is 77∘.what is the measure of the exterior angle at a (in degrees)?

Im literally having a mental breakdown

What is the solution to this system of equations? y= 2x - 3.5 x - 2y = -14