This question is confusing and I can’t seem to wrap my head around it, can someone answer it?

If f(x)= 3x+6 which of the following is the inverse of f(x)

In the 30-60-90 triangle below side s has a length of and side r has a length

Offering 30 if a plus b plus c equals 68 and ab plus bc plus ca equals 1121, where a, b, and c are all prime numbers, find the value of abc. the answer is 1978 but i need an explanation on how to get that.