A parabola passes through 3 points, (0,3), (2, 5) and (-1, 8). Form a system of equations and solve to find the equation of the parabola.

Question

Use gaussian elimination to solve. 

Answer 1

y = ax² + bx + c

When you substitute each of the ordered pairs, you get an equation involving a,b,c.

Doing this gives you three linear equations with those 3 unknowns.

Solve that 3 by 3 system any way you can; personally, I'd use the augmented matrix RREF method on my old TI-83 graphing calculator. If required to do it on paper, I might use determinants & Cramer's rule.

Check your answers.