Patterns in Polynomials

How patterns make multiplying and factoring polynomials easier?

  • Algebra tiles are helpful when trying to figure out which signs are being multiplied.Whenever there’s a positive and a positive multiplying for example (x+2)(x+3), the algebra tiles will all be colored in.

_20160421_200341Whenever there’s a negative and a positive multiplying for example (x-2)(x+3), the algebra tiles will look like half is colored and half is not.

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Lastly, whenever there’s 2 negatives multiplying for example (x-2)(x-3), the algebra tiles will look like half colored, half not, half colored and half not. _20160421_200244When factoring polynomials, you have to make sure the second term is half of the first term for example, x^2+5x+6 (the variable in the middle needs to have half of the number of x’s as the leading term). An example that would not factor would be (x^3+5x+6) because x^3 is 3 times x, not 2. How you get x^2 is by multiplying (x)(x), how you get 6x is adding the constants together and x, and finally how you get 8 is by multiplying the constants (so that means the #s have to multiply to one # and add to the other). Notice it’s using the same variable. _20160421_204754_20160421_200214Doesn’t matter which order they are in. 2+3+5 gives the same answer as 3+2+5…

_20160421_200157Other quick tips… to factor an equation with only 2 terms, it would have to have conjugates and a negative. Example (x-4)(x+4) = x^2-16 (two terms). And double patterns are a thing!—— x^2+4xy+3y^2=(x+y)(x+3y)