Answer:
We know that the sum of the angles in a triangle is 180 degrees. Therefore, we can write:
m∠A + m∠B + m∠C = 180
Substitute the given values:
5x+6 + 7x-18 + m∠C = 180
Combine like terms:
12x-12 + m∠C = 180
Add 12 to both sides:
12x + m∠C = 192
Subtract 12x from both sides:
m∠C = 192 - 12x
Therefore, m∠C is equal to 192 minus 12 times x.