Question

Multiply: (x – 4)(x + 5)

(a) x2 + 5x - 20,

(b) x2 - 4x - 20,

(c) x2 - x - 20,

(d) x2 + x - 20.
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Answer 1

$\huge \bold \color{red} \mathfrak{answer} :$

$(x - 4)(x + 5) \: \: \\ \implies x(x + 5) - 4(x + 5) \\ \implies {x}^{2} + 5x - 4x - 20 \\ \implies {x}^{2} + x - 20$

$\bold{so \: option \:d \: is \: Correct \: }$