Multiplying Polynomials

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Multiplying Polynomials
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How do we find the area of a square?
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• The correct formula is written above.
• Use it to find the area of the square below.

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• As we have already said, to find the area, we
• square the length of a side.

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What happens to the area if we add 3 units to the
length and 1 unit to the width?
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This definitely increases the area. How can we
find the area of the new shape?
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One way would be to add the areas of the
individual rectangles that we have formed.
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(No Transcript)
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Another way of doing this would be using the
formula for the area of a rectangle?
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Alw
A(x3)(x1)
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• How do we get from (x3)(x1) to
  ?
• We have already seen that 2(x1) 2x2
• We were able to do this multiplication by using
  the
• distributive property. We can also use the
• distributive property when we are multiplying
• polynomials by polynomials.

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• We need to remember to distribute each
• term in the first set of parentheses through
• the second set of parentheses.
• Example
• (X3)(x1)(x)(x)(x)(1)(3)(x)(3)((1)

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Lets work a few of these.

• 1.) (x2) (x8)
• 2.) (x5) (x-7)
• 3.) (2x4) (2x-3)

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Check your answers.

• 1.) (x2) (x8) X210x16
• 2.) (x5) (x-7) X2-2x-35
• 3.) (2x4) (2x-3) 4x22x-12

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By learning to use the distributive property, you
will be able to multiply any type of polynomials.

• Example (x1)(x22x3)
• (x1)(x22x3) X32x23xx22x3