# TSI Math: Solving a Quadratic Equation for *x*

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What is x for the equation 2x² + 36 = -18x?

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

going to put the zero thing he over here right

So it might help to pretend that we're kali's hurting

the terms to the left side like sheep And we're

adding eighteen acts to both sides there See if we

do that we get to x squared plus eighteen ax

plus thirty six equal zero Okay Since each term of

this quadratic is divisible by two well let's divide both

sides of the equation by two to simplify the factoring

process knows that the right side remains equal to zero

since zero Divided by two in california is zero so

we get x squared plus nine x plus eighteen Now

we need two factors of the constant term eighteen that

add up to the ex coefficient nine what are they

Well what times What is eighteen Well could it be

two and nine Yes but it's not one in eighteen

Yes but it's not And yes it's three and six

and conveniently three plus six is nine So it looks

like that explosive six and then explodes three zero Well

the final staff is set Each factor equals zero and

salt for acts right So if x plus six zero

than x cast to be a minus six And similarly

three has to be minus three They're the solution given

Equation is x equals negative six comma negative three and

that's it The answer is b and don't get fooled

by the others because they all use the wrong factors

to get eighteen and other mistakes like that So answer

is b but but