What is the value of b and c?

Step-by-step explanation:

By the markings, this is an isosceles triangle.  That means that angle R and angle T have the same exact measures since the sides across from those angles have the same measure.  That means that angle T, or b, is 73 degrees.

Since, by the Triangle Angle-Sum Theorem, all angles in any triangle have to add up to equal 180 degrees, then angle S, or c, is 180 - 73 - 73 which is 34 degrees.