189k views
1 vote
THIS IS AN ESSAY NOT JUST AN ANSWER

Prompt:
What does it mean to multiply polynomials?
Explain how to multiply (x + 2) (X - 4) as if you're teaching a student a year
younger than you.

2 Answers

1 vote

We can simply use distributive law of grade 1

  • (a+b)(c+d)=ac+ad+bc+bd

I assume you know multiplication of monomials

So

  • (x+2)(x-4)
  • x(x-4)+2(x-4)
  • x²-4x+2x-8
  • x²-2x-8
User Jay Elston
by
6.5k points
4 votes

Answer:

  • We assume before this you have learned how to multiply two monomials and monomial with binomial.

Use the following formula to multiply binomials:

  • (a + b)(c + d) = ab + ad + bc + bd

Applied to the given expression, we have:

  • (x + 2)(x - 4), where a = x, b = 2, c = x , d = -4

Expand as indicated above:

  • (x + 2)(x - 4) =
  • x(x) + x(-4) + 2(x) + 2(-4)

Now simplify

  • x² - 4x + 2x - 8

Collect like terms, (-4x) and (2x):

  • x² + (-4x + 2x) - 8 =
  • x² - 2x - 8

This is how you can do same order operations with any binomials.

User Futu
by
7.3k points
Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.