# Find the function by knowing three points on the graph

• March 17th 2011, 11:05 AM
Anna55
Find the function by knowing three points on the graph
A quadratic function goes through the points (2,3) (3,4) (6,-5). Find the function. Please help me with this.
• March 17th 2011, 11:15 AM
topsquark
Quote:

Originally Posted by Anna55
A quadratic function goes through the points (2,3) (3,4) (6,-5). Find the function. Please help me with this.

$y = ax^2 + bx + c$

So using (2, 3):
$3 = 4a + 2b + c$

Do this for all three points and you will have three equations in the unknown variables a, b, and c.

-Dan
• March 17th 2011, 01:35 PM
Anna55
Thank you I understand now.