Question

PLEASE HELP! I understand the FOIL method but I don't get this.
Write the product as a trinomial.
(k – 1)(k – 4)

Answer 1

What happens when you use the foil method?

Answer 2

k^2-5k+4

Answer 3

i believe, you just foil out and pretend the variables are constant.

Answer 4

If you understand the foil method, then can you do it?

Answer 5

Actually, my question is, do I keep the minus signs? and subtract it all once I'm done with the FOIL method

Answer 6

Okay, so foil method gives you:\[
(k – 1)(k – 4) = k\times k+-1 \times k +k\times -4 + -1\times -4
\]

Answer 7

Then you just have to simplify.

Answer 8

\[
=k^2-k-4k+4 = k^2-5k+4
\]

Answer 9

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