Zeros of a quadratic, and writing one from its zeros or from a vertex and a point
Grade 9 Math Worksheet - Challenge Me

Circle the best answer, or write your answer on the line.
Zee's swing graph crosses the x-axis at -5 and -2 and passes through (-6, 16). Write it as y = ax² + bx + c. Write a, b and c, in that order, with commas.
Esme's rocket graph crosses the x-axis at -1 and 5 and passes through (3, 32). Write it as y = ax² + bx + c. Write a, b and c, in that order, with commas.
“The vertex is (2, 9)” Jun's table for a rainbow arc shows its vertex and two mirror rows. Write it as y = ax² + bx + c. Write a, b and c, in that order, with commas.
“The vertex is (1, -12)” Kira's table for a basketball shot shows its vertex and two mirror rows. Write it as y = ax² + bx + c. Write a, b and c, in that order, with commas.
“The vertex is (2, -9)” Luz's table for a bowl shows its vertex and two mirror rows. Write it as y = ax² + bx + c. Write a, b and c, in that order, with commas.
“The vertex is (-3, 12)” Milo's table for a ramp dip shows its vertex and two mirror rows. Write it as y = ax² + bx + c. Write a, b and c, in that order, with commas.
Noah graphs a valley on a grid. Which equation makes this graph?
- y = -9(x + 2)(x - 4)
- y = (x + 2)(x - 4)
- y = -(x + 2)(x - 4)
- y = (x - 2)(x + 4)
Pia graphs a deep bowl on a grid. Which equation makes this graph?
Graph on a grid (each square is one unit): a parabola opening up, crossing the x-axis at (1, 0) and (5, 0), with vertex (3, -8). Graph on a grid (each square is one unit): a parabola opening up, crossing the x-axis at (1, 0) and (5, 0), with vertex (3, -8). 0 1 2 3 4 5 6 −9 −8 −7 −6 −5 −4 −3 −2 −1 1 - y = 2(x - 1)(x - 5)
- y = 2(x + 1)(x + 5)
- y = (x - 1)(x - 5)
- y = -2(x - 1)(x - 5)
Ren graphs a rainbow on a grid (it is a small rainbow). Which equation makes this graph?
Graph on a grid (each square is one unit): a parabola opening down, crossing the x-axis at (-3, 0) and (1, 0), with vertex (-1, 4). Graph on a grid (each square is one unit): a parabola opening down, crossing the x-axis at (-3, 0) and (1, 0), with vertex (-1, 4). −5 −4 −3 −2 −1 1 2 3 −1 1 2 3 4 5 0 - y = -(x + 3)(x - 1)
- y = -(x - 3)(x + 1)
- y = (x + 3)(x - 1)
- y = 4(x + 3)(x - 1)
Tala graphs a tent roof on a grid. Which equation makes this graph?
Graph on a grid (each square is one unit): a parabola opening down, crossing the x-axis at (0, 0) and (6, 0), with vertex (3, 18). Graph on a grid (each square is one unit): a parabola opening down, crossing the x-axis at (0, 0) and (6, 0), with vertex (3, 18). −1 1 2 3 4 5 6 7 2 4 6 8 10 12 14 16 18 20 0 - y = -x(x - 6)
- y = -2x(x - 6)
- y = 2x(x - 6)
- y = -2x(x + 6)

