What is a formula for a function that squares any reciprocal and, if possible, takes the reciprocal of that nunber

Perform the required operations on the following functions given: f(x)= 3-x; g(x)= -2x find g[f(x)]

Cassie is traveling 675 miles today to visit her brother and his family. so far, she has stopped for gas three times. at the first stop, she put in 7.1 gallons of gas and paid $23.79. at her second stop, she put in 5.8 gallons of gas and paid $19.08. and, at the third stop, 6.6 gallons and paid $20.39. at which stop did casey pay the most for gas?

Solve this equation using substitution. {4x + y = −2} {4x + 6y = 44}