Factoring difference of squares: $x^2 - y^2$

Lessons

• Introduction
  What is a "difference of squares"?

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• 1.
  Factor:
  a)

  ${x^2} - 49$
  
  
  b)

  $4{x^2} + 25$
  
  
  c)

  $16 - 9{x^2}$
  
  

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• 2.
  Factor:
  a)

  $100{x^2} - 49{y^2}$
  
  
  b)

  $32{x^2} - 242{y^2}$
  
  
  c)

  $2{a^3}b - 8a{b^3}$
  
  
  d)

  $25{a^2}{b^2} - 4{c^2}$
  
  

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• 3.
  Factor:
  a)

  ${\left( {x - y} \right)^2} - {\left( z \right)^2}$
  
  
  b)

  ${\left( {5a + 6b} \right)^2} - {\left( {9a - b} \right)^2}$
  
  
  c)

  $169{\left( {x - 3} \right)^2} - 25{\left( {x + 6} \right)^2}$
  
  

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• 4.
  Factoring "difference of squares" more than once
  
  Factor:
  a)

  ${x^4} - 16$
  
  
  b)

  $162{a^4} - 2{b^4}$
  
  
  c)

  $5{a^7}{b^8} - 80{a^3}{c^4}$
  
  

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