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ANSWER

The two numbers are 128 and 128

EXPLANATION

Let the two numbers be x and y.

We have that:

[tex]\begin{gathered} x+y=256 \\ x\cdot y=A \end{gathered}[/tex]

where A is a maximum.

From the first equation:

[tex]x=256-y[/tex]

Substitute that into the second equation:

[tex]\begin{gathered} (256-y)\cdot y=A \\ \Rightarrow256y-y^2=A \\ \Rightarrow y^2-256y+A=0 \end{gathered}[/tex]

The equation above is a quadratic equation in the general form:

[tex]ax^2+bx+c=0[/tex]

The parabola is downward facing and so, its vertex will be the maximum.

We can find the vertex (x, y) of the parabola by using:

[tex]x=\frac{-b}{2a}[/tex]

In the case given, the vertex can be found by using:

[tex]\begin{gathered} y=\frac{-(-256)}{2(1)}=\frac{256}{2} \\ y=128 \end{gathered}[/tex]

Recall that:

[tex]x=256-y[/tex]

Therefore, we have that:

[tex]\begin{gathered} x=256-128 \\ x=128 \end{gathered}[/tex]

Hence, the two numbers are 128 and 128.