# TSI Math: Solving a Difference of Two Squares

Which of the following are the solutions to the equation 9z² – 4 = 0?

Intermediate Algebra and Functions | Quadratic and Other Polynomial Expressions, Equations, and Functions |

Mathematics and Statistics Assessment | Quadratic and Other Polynomial Expressions, and Functions |

Product Type | TSI |

TSI | Mathematics and Statistics Assessment TSI Math TSI Mathematics |

TSI Math | Intermediate Algebra and Functions |

TSI Mathematics | Intermediate Algebra and Functions |

Test Prep | TSI |

### Transcript

minus b squared that factors into a plus b a

minus b like that right Well ninety squared minus four

fits this form perfectly because both ninety squared and for

our perfect squares a and b square roots of each

term so equals three and b equals two And then

we could just plug and chug those values into the

general form to bring some peace to this you know

conflict the difference So a plus b times quantity a

minus b zero and then we've got three c plus

teo and i'm twenty three z minus two not zero

And then well we'll hug out a solution by setting

each factor equal to zero So three z plus two

zero that means three ze is negative too And z

is negative Two thirds got it so then three z

minus two is zero and three ze is too And

then z is just two thirds Okay well the solutions

have become such good friends They now refuse to be

separated because they have the same value But opposite signs

you know like opposites attract and a magnet thing you

know yeah right Um is z equals plus or minus

two thirds Yeah the answer is c as in cuddling