Question

factorise the following
$z {}^{2} +4z - 12 \\ y {}^{2} - 16y - 80 \\ 5 {x}^{2} - 29xy - 42 {x}^{2} \\ 9 - 18x - 8{x}^{2} \\ {a}^{4 } - 3a {}^{2} + 2 \\ 8m {}^{3} - 2m {}^{2} n - 15mn$
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Answer 1

Answer:

1. z^2 + 4z -12

z^2 +6z -2z -12

z ( z+6) -2 ( z+6)

(z+6) (z-6)