The diagram represents the polynomial [tex][tex]$4x^2 + 23x - 72$[/tex][/tex]. What is the factored form of [tex][tex]$4x^2 + 23x - 72$[/tex][/tex]?

[tex]\[
\begin{tabular}{|c|c|c|}
\cline{2-3}
\multicolumn{1}{c|}{} & ? & ? \\
\hline
? & [tex]$4x^2$[/tex] & [tex]$32x$[/tex] \\
\hline
? & [tex]$-9x$[/tex] & [tex]$-72$[/tex] \\
\hline
\end{tabular}
\][/tex]

A. [tex][tex]$(4x + 8)(x - 9)$[/tex][/tex]
B. [tex][tex]$(4x - 8)(x + 9)$[/tex][/tex]
C. [tex][tex]$(4x + 9)(x - 8)$[/tex][/tex]
D. [tex][tex]$(4x - 9)(x + 8)$[/tex][/tex]



Answer :

To factorize the polynomial [tex]\( 4x^2 + 23x - 72 \)[/tex], we need to identify the correct factored form among the given options.

Let's examine each option to determine which one properly reconstitutes the given polynomial when expanded:

1. [tex]\((4x + 8)(x - 9)\)[/tex]:
[tex]\[ (4x + 8)(x - 9) = 4x \cdot x + 4x \cdot (-9) + 8 \cdot x + 8 \cdot (-9) \\ = 4x^2 - 36x + 8x - 72 \\ = 4x^2 - 28x - 72 \][/tex]
This does not match [tex]\(4x^2 + 23x - 72\)[/tex].

2. [tex]\((4x - 8)(x + 9)\)[/tex]:
[tex]\[ (4x - 8)(x + 9) = 4x \cdot x + 4x \cdot 9 + (-8) \cdot x + (-8) \cdot 9 \\ = 4x^2 + 36x - 8x - 72 \\ = 4x^2 + 28x - 72 \][/tex]
This does not match [tex]\(4x^2 + 23x - 72\)[/tex].

3. [tex]\((4x + 9)(x - 8)\)[/tex]:
[tex]\[ (4x + 9)(x - 8) = 4x \cdot x + 4x \cdot (-8) + 9 \cdot x + 9 \cdot (-8) \\ = 4x^2 - 32x + 9x - 72 \\ = 4x^2 - 23x - 72 \][/tex]
This does not match [tex]\(4x^2 + 23x - 72\)[/tex].

4. [tex]\((4x - 9)(x + 8)\)[/tex]:
[tex]\[ (4x - 9)(x + 8) = 4x \cdot x + 4x \cdot 8 + (-9) \cdot x + (-9) \cdot 8 \\ = 4x^2 + 32x - 9x - 72 \\ = 4x^2 + 23x - 72 \][/tex]
This matches [tex]\(4x^2 + 23x - 72\)[/tex].

Therefore, the factored form of the polynomial [tex]\( 4x^2 + 23x - 72 \)[/tex] is [tex]\((4x - 9)(x + 8)\)[/tex]. Thus, it matches the fourth option provided in the question.