How do you factor the trinomial $3c^2 - 1c - 24$ ?

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Answer 1 · 2016-05-04T17:40:34

$color(green)((3c + 8) (c - 3)$ is the factorised form of the expression.

$3c^2 - 1c - 24$

We can Split the Middle Term of this expression to factorise it.

In this technique, if we have to factorise an expression like $xa^2 + ya + z$ , we need to think of 2 numbers such that:

$N_1*N_2 = x*z= 3*(-24) = -72$

AND

$N_1 +N_2 = y = -1$

After trying out a few numbers we get $N_1 = -9$ and $N_2 =8$

$(- 9)*8 = -72$ , and $8 + (-9)= -1$

$3c^2 - 1c - 24 = 3c^2 - 9c + 8c - 24$

$=3c (c - 3) + 8 (c - 3)$

$= color(green)((3c + 8) (c - 3)$

How do you factor the trinomial 3c^2 - 1c - 24 3c^2 - 1c - 24 ?