Answer:
[tex]\text{(a) } x=11,\\\text{(b) } \angle C=12^{\circ}[/tex]
Step-by-step explanation:
The sum of the interior angles in a triangle is always equal to 180 degrees. Therefore, we have the following equation:
[tex](3x+28)+(5x+52)+(2x-10)=180[/tex]
Solving for [tex]x[/tex]:
[tex](3x+28)+(5x+52)+(2x-10)=180,\\3x+28+5x+52+2x-10=180,\\10x+70=180,\\10x=110,\\x=\boxed{11}[/tex]
Substitute [tex]x=11[/tex] to solve for angle C:
[tex]m\angle C=2x-10,\\m\angle C=2(11)-10,\\m\angle C==22-10=\boxed{12^{\circ}}[/tex]