# How do you find a quadratic function whose vertex is at the point (2,9) and has the given x intercepts (1,0) & (3,0)?

##### 1 Answer

Jun 7, 2015

You've got to know the vertex form of a quadratic function!

Every quadratic function can be expressed in the standard form

Using factoring and completing the square, many Algebra textbooks will give you a rewritten form of the above equation:

Because

The roots let us solve for

Therefore