Question

Given three points (-2,2), (-1,-1),(2,6) how do you write a quadratic function in standard form with the points?

Answer 1

`y=4/3*x^2+x-4/3=(4x^2+3x-4)/3`

Explanation:

Searched quadratic function is `y=ax^2+bx+c`

After imposing conditions,

`4a-2b+c=2`, `a-b+c=-1` and `4a+2b+c=6`

After solving this equation system,

`b=1`, `a=4/3` and `c=-4/3`

Thus, `y=4/3*x^2+x-4/3=(4x^2+3x-4)/3`