The quadratic function is .

For this function a = , so the graph opens down and the function has a maximum value.

The maximum value of the function is the y-coordinate of the vertex.

The - coordinate of the vertex is .

        (Substitute the values a = and b = 10)

      (Simplify) The y-coordinate of the vertex by evaluating the function for = 1.25.

                  (Original function)

        ( =   1.25)

            (Simplify)

or

The maximum value of the function is .

The domain is all real numbers.

The range is all real numbers less than or equal to maximum value ,or .

The function has maximum value.

The maximum value of the function is .

The domain is all real numbers.

The range is .