How do you factor #x²-2x-8#?

1 Answer
Shantelle
May 3, 2018

#(x-4)(x+2)#

Explanation:

#x^2 - 2x - 8#

To factor something, we should first make sure that it is in the form of #ax^2 + bx + c# to make it easier, which this expression is in.

Then, we have to find two numbers that:

  • Add up to #b# (or in this case, #-2#)
  • Multiply up to #a * c# (or in this case, #1 * -8 = -8#

Those two numbers are #-4# and #2#:

  • #-4 + 2 = -2#
  • #-4 * 2 = -8#

Now we put them into factored form, which is: #(x-4)(x+2)#.

Hope this helps!

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