Graph y = ax^2 + bx + c, and match equations, tables and graphs

Answer Key - Grade 9 Math Worksheet - Building Confidence

Circle the best answer, or write your answer on the line.

1. 1.

   Ari plots a skate ramp dip with y = x² - 4x + 1. What is the output in the table row with input -2?

   13
2. 2.

   Bo draws the curve of a giant soup bowl with y = x² + 6x + 2 (soup not included). What is the output in the table row with input -5?

   -3
3. 3.

   Esme graphs a swing's path with y = x² - 2x - 5. What is the output in the table row with input -4?

   19
4. 4.

   Jun maps a dip in a bike trail with y = x² + 5x - 3. What is the output in the table row with input -2?

   -9
5. 5.

   Kira graphs a bowl with y = 2x² - 12x + 5. Its mirror (axis of symmetry) is x = -b/(2a), with a = 2 and b = -12. What is that x?

   3
6. 6.

   Luz maps a valley with y = x² + 8x + 3. Its mirror (axis of symmetry) is x = -b/(2a), with a = 1 and b = 8. What is that x?

   -4
7. 7.

   Milo sketches a rainbow, y = -2x² + 12x + 1 (colors later). Its mirror (axis of symmetry) is x = -b/(2a), with a = -2 and b = 12. What is that x?

   3
8. 8.

   Noah graphs a swing with y = 3x² - 30x + 4. Its mirror (axis of symmetry) is x = -b/(2a), with a = 3 and b = -30. What is that x?

   5
9. 9.

   Pia graphs y = -x² + 6x - 2 to plan a rainbow mural. Does the graph open up or down?

   • Up, because b = 6 is above 0
   • Up, because x² is never negative
   • Down, because a = -1 is below 0
10. 10.

    Ren graphs y = 2x² - 8x - 3 for a bowl design. Does the graph open up or down?

    • Down, because c = -3 is below 0
    • Down, because b = -8 is below 0
    • Up, because a = 2 is above 0