Haley substituted the values of a, b, and c into the quadratic formula below.

The quadratic formula is x equals negative b plus or minus the square root of b squared minus four times a times c, all over 2a. 
Looking at the equation, we can find the values for a, b, and c
a=7
b= -10
c= -2

So then putting that back into standard form, which is ax^2+bx+c, we know Haley's function in standard form is 7x^2-10x-2