In which table is Y a nonlinear function of X?

Show algebraically that f and g are inverse functions f(x)=x^2/-6; g(x)=square root of 2x+12

You paid 28.00 for 8 gallons of gasoline. how much would you pay for 15 gallons of gasoline?

Suppose that sahil knows that 45 people with ages of 18 to 29 voted. without using a calculator, he quickly says then 135 people with ages of 30to 49 voted. is he correct? how might sohil have come up with his answer so quickly?