Question

how do i write a quadratic function in standard form when i'm given the x-intercepts 1 and 9.

Answer 1

Answer:

y = x² - 10x + 9

Explanation:

The x-intercepts are 1 and 9

A quadratic equation is of the form

$y=ax^2+bx+c$

When x-intercept is 1

x-intercept = (1, 0)

The factor can be written as (x - 1)

When x-intercept is 9

x -intercept = (9, 0)

The factor can be written as (x - 9)

The equation y is a multiplication of the factors

y = (x - 1)(x - 9)

Expand the equation

$\begin{gathered} y=x^2-9x-x+9 \\ y=x^2-10x+9 \end{gathered}$

Therefore, the quadratic equation in standard form is:

y = x² - 10x + 9