Question

the diagram shows a triangle.
what is the value of c?
c = \boxed{\space}^\circ

Explanation:

Step1: Sum angles to 180°

$83^\circ + (c+15^\circ) + (2c-2^\circ) = 180^\circ$

Step2: Simplify left side

$83 + c + 15 + 2c - 2 = 180$
$3c + 96 = 180$

Step3: Solve for $c$

$3c = 180 - 96$
$3c = 84$
$c = \frac{84}{3}$

Answer:

$28$