Plz help this is hard

Prove that the sum of two consecutive exponents of the number 5 is divisible by 30.if two consecutive exponents are 5n and 5n + 1, then their sum can be written as 30.

When using the linear combination metho e linear combination method to solve a system of linear equations, the four options are:

Which describes the difference between the graph of f(x)=x^2 and g(x)=-(x^2-2)