How do you factor the trinomial $a^2 - a - 20$ ?

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Answer 1 · 2015-12-01T21:31:51

Factor y = a^2 - a - 20.

Ans: (a + 4)(a - 5)

Factor: $y = a^2 - a - 20.$
Fin 2 numbers knowing sum (-1) and product (-20). They are (4) and (-5).
y = (a + 4)(a - 5).

How do you factor the trinomial a^2 - a - 20a^2 - a - 20?