C programming - parabola. HELP!!!!

This is an exercise that i cannot figure out for the life of me... someone who is more competent than me in C programming please help!!!

What to do:

The equation of the parabola is

y = ax2 + bx + c

Write a complete C program capable of finding the maximum or

minimum of a parabola. As input, the program is to ask the user

data consisting of the values of a, b and c for the parabola.

Find the minimum value (or maximum depending on the parabola)

of y for all values of x between -20.0 and +20.0 in increments

of 0.01.

Your program must produce a nicely aligned report. Display the

minimum/maximum value of y and the value of x at that point.

Display your name(s) at the bottom of the report.

Your code must have good style including comments and proper

indentation.

All numerical values on the report must come from variables,

not constants.

equation max/min of y value of x

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y = 1.1x*x – 2x + 1 0.09 (min) 0.91

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