Observe the graph:
\From graph the vertex is .
The vertex and one additional point on the graph of the quadratic function.
\ Quadratic function in vertex form .
Substitute ,
in
.
Find the value of .
The parabola passes through point .
Substitute for ,
in
.
\
Substitute for ,
and
in
.
The quadratic function is .
.
The quadratic function is .