Question

the diagram shows a triangle.
what is the value of c?
c = \square^\circ

Explanation:

Step1: Sum angles to 180°

$$(2c+33^\circ)+(2c+9^\circ)+(2c+6^\circ)=180^\circ$$

Step2: Combine like terms

$$6c + 48^\circ = 180^\circ$$

Step3: Isolate term with $c$

$$6c = 180^\circ - 48^\circ$$
$$6c = 132^\circ$$

Step4: Solve for $c$

$$c = \frac{132^\circ}{6}$$

Answer:

$c = 22^\circ$