What is the best approximation of the solution to the equations that these two lines represent

If a distance of 75 yds is measured back from the edge of the canyon and two angles are measured , find the distance across the canyon angle acb = 50° angle abc=100° a=75 yds what does c equal?

Can anyone me with this question?

Which statement is true about the discontinuities of the function f(x) = x-5/ 3x^2-17x-28