Question

Write the equation of a quadratic that has x-intercepts of (-2,0) and (4,0), a vertical stretch of 2, and the vertex is a maximum.

Factored form:
Standard (Expanded) form:

Answer 1

The standard form of a quadratic function presents the function in the form

f

(

x

)

=

a

(

x

−

h

)

2

+

k

where

(

h

,

k

)

is the vertex. Because the vertex appears in the standard form of the quadratic function, this form is also known as the vertex form of a quadratic function.

The standard form is useful for determining how the graph is transformed from the graph of

y

=

x

2

. The figure below is the graph of the basic function

Explanation: