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SOLUTION
[tex]x^2-3x-40[/tex]
Get two numbers whose sum and product are -3 and -40 respectively;
[tex]The\text{ numbers are -8 and 5}[/tex]
To factorize;
[tex]\begin{gathered} x^2-8x+5x-40 \\ x(x-8)+5(x-8) \\ (x+5)(x-8) \end{gathered}[/tex]
OPTION B IS THE CORRECT ANSWER.
