# TSI Math: Recognizing the Axis of Symmetry in a Quadratic Equation

What is the axis of symmetry of the parabola given by the equation -3x² + 42x – y = 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

y equals mx plus b So here it is y

equals negative three x squared plus forty two x What

when a quadratic equation is written in the form why

equals a x squared plus b x plus c the

access of symmetry by definition here is the line x

equals negative b over two a and like you just

had to know that formula The vertical line passes through

the vertex in the middle of the problem right there

So here b is forty two and a is well

negative three so we've got negative forty two overnegative six

there and that equals seven So thie axis of awesome

for the given parable of there is x equal seven

and that's it The answer is c