Help please!!:) please and thank you.

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.

What is the effect on the graph of the function f(x)=x when f(x) is replaced with -f(x)+4

Equation for the calculation double 2 and then add 5