Please can someone help me on this ASAP pls.

Solve the system by the elimination method. 2x + y - 4 = 0 2x - y - 4 = 0 when you eliminate y, what is the resulting equation? a. x = 0 b.4x = -8 c.4x = 8

Which expression is equivalent to (3^2)^-2 a.-81 b.-12 c.1/81 d.1/12

Tom wants to order tickets online so that he and three of his friends can go to a water park the cost of the tickets is 16.00 per person there is also a 2.50 one-time service fee for ordering tickets online write an expression in term of n that represents the cost for n ordering tickets online