### Answers − Quadratic Graphs using x and y axis − 2

#### 1. Draw the graph y = 2x^{2} + 10x + 8

(a) The graph crosses the y axis at the number term c which is 8. When x = 0 then y = 8. The coordinate is (0, 8) |

(b) The graph crosses the x axis where 2x^{2} + 10x + 8 = 0. Refer to question 1 of Solve Quadratics by Factorising - 2. So y = 0 when x = −4 or −1.The coordinates are (−4, 0) and (−1, 0) |

(c) Draw the graph using the above coordinates |

#### 2. Draw the graph y = 3x^{2} + 21x + 18

(a) The graph crosses the y axis at the number term c which is 18. When x = 0 then y = 18. The coordinate is (0, 18) |

(b) The graph crosses the x axis where 3x^{2} + 21x + 18 = 0. Refer to question 2 of Solve Quadratics by Factorising - 2. So y = 0 when x = −6 or −1.The coordinates are (−6, 0) and (−1, 0) |

(c) Draw the graph using the above coordinates |

#### 3. Draw the graph y = 4x^{2} + 20x − 24

(a) The graph crosses the y axis at the number term c which is −24. When x = 0 then y = −24. The coordinate is (0, −24) |

(b) The graph crosses the x axis where 4x^{2} + 20x − 24 = 0. Refer to question 3 of Solve Quadratics by Factorising - 2. So y = 0 when x = −6 or 1.The coordinates are (−6, 0) and (1, 0) |

(c) Draw the graph using the above coordinates |

#### 4. Draw the graph y = 2x^{2} + 9x − 56

(a) The graph crosses the y axis at the number term c which is −56. When x = 0 then y = −56. The coordinate is (0, −56) |

(b) The graph crosses the x axis where 2x^{2} + 9x − 56 = 0. Refer to question 4 of Solve Quadratics by Factorising - 2. So y = 0 when x = −8 or ^{7}/_{2}.The coordinates are (−8, 0) and ( ^{7}/_{2}, 0) |

(c) Draw the graph using the above coordinates |

#### 5. Draw the graph y = 5x^{2} − 20x − 60

(a) The graph crosses the y axis at the number term c which is −60. When x = 0 then y = −60. The coordinate is (0, −60) |

(b) The graph crosses the x axis where 5x^{2} − 20x − 60 = 0. Refer to question 5 of Solve Quadratics by Factorising - 2. So y = 0 when x = −2 or 6.The coordinates are (−2, 0) and (6, 0) |

(c) Draw the graph using the above coordinates |

#### 6. Draw the graph y = 3x^{2} − 21x + 36

(a) The graph crosses the y axis at the number term c which is 36. When x = 0 then y = 36. The coordinate is (0, 36) |

(b) The graph crosses the x axis where 3x^{2} − 21x + 36 = 0. Refer to question 6 of Solve Quadratics by Factorising - 2. So y = 0 when x = 3 or 4.The coordinates are (3, 0) and (4, 0) |

(c) Draw the graph using the above coordinates |

#### 7. Draw the graph y = 3x^{2} − 40x + 48

(a) The graph crosses the y axis at the number term c which is 48. When x = 0 then y = 48. The coordinate is (0, 48) |

(b) The graph crosses the x axis where 3x^{2} − 40x + 48 = 0. Refer to question 7 of Solve Quadratics by Factorising - 2. So y = 0 when x = ^{4}/_{3} or 12.The coordinates are ( ^{4}/_{3}, 0) and (12, 0) |

(c) Draw the graph using the above coordinates |

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