In ΔCDE, m∠C = (9x+11) ^{/circ} (9x+11) ∘, m∠D = (3x-15) ^{/circ} (3x-15) ∘, and m∠E = (2x+16) ^{/circ} (2x+16) ∘. What is the value of x?

x = 12

Step-by-step explanation:

The sum of the 3 angles in a triangle = 180°

Sum the 3 given angles and equate to 180, that is

9x + 11 + 3x - 15 + 2x + 16 = 180, simplify left side

14x + 12 = 180 (subtract 12 from both sides)

14x = 168 (divide both sides by 14)

x = 12