triangle angle problems

[starwolf]

I can't get this problem-

triangle ABC. m<A=x+30, m<B=2x-4, and m< of the exterior angle at C is 6x-52. Find m<ACB

 

[pka]

The measure of any exterior angle of a triangle equals the sum of the measures of the two remote interior angles.
Solve for x. Then find angle ACB.