Need help with math who is up brainlest and points pls hurry

Rewrite the following quadratic functions in intercept or factored form. show your work. f(x) = 3x^2 - 12

Is there an x intercept in the equation 60*1.15^x

Charlie is at an amusement park that has 18 different rides. each ride costs $1.75. the function c(r) = 1.75r represents the total amount of money that charlie will spend if he goes on r rides, but he never goes on the same one more than once. what domain and range are reasonable for the function?