Question

3x^2-12x factorise in the form (x+b)(x-b)

Answer 1

Answer:

$3x(x-4)$

Step-by-step explanation:

$3x^2-12x$  cannot be factorised in the form (x+b)(x-b) unless one of the b's is zero, so I wonder if the expression is incomplete?

To factorise $3x^2-12x$, take out the common factor $3x$:

$\implies3x(x-4)$

Therefore, x = 0 and x = 4

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$3x^2-12x$  factorised in the form (x+b)(x-b) would be $(3x+0)(x-4)$

but it is not usual to have a zero in a factorised form.