Answer:
c = 13
Explanation:
We can solve for c using an equation that models the sum of the interior angles of a triangle.
The interior angles of a triangle add to 180º. Therefore, we can construct the equation:
90 + (3c - 1) + 52 = 180
Then, we can solve for c algebraically.
(3c - 1) = 180 - 90 - 52
3c - 1 = 38
3c = 38 + 1
3c / 3 = 39 / 3
c = 13