What is 15 and three fourths simplified as

Given f(x) = 2x^2- 5x+1, determine the function value f(2). do not f(x) = in your answer

How do i simply this expression (quadratic formula basis) on a ti-84 or normal calculator?

Agroup of three friends order a combo meal which includes two slices of pizza and a drink each drink is priced at $2.50 the combined total of $31.50 how much is the cost of a slice of pizza