On 4-7 how do you write the ratio and find the answer?

Basic trig concepts you have to keep in mind:
SOH CAH TOA
Sine: Opposite of the angle over the hypotenuse
Cosine: Adjacent over hypotenuse
Tangent: Opposite over adjacent
I'll do one of the problems, you should be able to do the rest (It's good practice ;))

This polygon has 4 sides
180(4-2) = 180(2) = 360 degree
80+90+2x + 3x = 360
170+5x = 360
5x = 190
x= 38
measure of angle t is 2(38)= 76
the answer is c. trust me
hope this !