Please help me every one

If g^-1(x) is the inverse of g (x) which statement must be true

Ahighway between points a and b has been closed for repairs. an alternative route between there two locations is to travel between a and c and then from c to b what is the value of y and what is the total distance from a to c to b?

What is the equation of a line that passes through points (0, 4) and (-4,-8)?