Last updated: October 22, 2026 · Written by the Math Made Easy math teachers

These 20 problems train standards F-IF.C.7a, F-IF.C.8a, F-IF.B.4 and A-SSE.B.3b. They start with reading features from vertex, standard and factored forms, then complete the square, graph parabolas and compare functions.
The last six problems model a launched ball, a fenced pen and a T-shirt sale, and write equations from given points.
Standards: F-IF.C.7a, F-IF.C.8a, F-IF.B.4, A-SSE.B.3b · Level: Grade 9 Algebra 1
Problem 1 Read the Vertex Form, Opening Up ★★★
Look at y = 2(x − 3)² + 5. Does its parabola open upward or downward? Name the turning point, the mirror line and the lowest or highest value of y.
Problem 2 Read the Vertex Form, Opening Down ★★★
The rule y = −(x + 4)² − 2 describes a parabola. Decide its direction of opening and name its turning point and its extreme value.
Problem 3 Axis from Standard Form ★★★
Locate the mirror line and the turning point of y = x² − 18x + 50.
Problem 4 Complete a Table of Values ★★★
Build a table of values for y = x² − 6x + 5 using x = 0, 1, 2, 3, 4, 5, 6. Use the table to name the turning point and the point on the y-axis.
Problem 5 Read the Factored Form ★★★
The function y = (x − 2)(x + 6) is in factored form. Read off where its graph meets the x-axis, then find the mirror line and the turning point.
Problem 6 Read a Parabola Graph ★★★
Study the parabola drawn below. Give its highest point, its mirror line, its largest y-value and where it meets the y-axis.
Problem 7 Vertex Form to Standard Form ★★★
Write y = 3(x − 1)² − 4 in standard form.
Problem 8 Vertex of a Downward Parabola ★★★
Find the highest point of the parabola y = −2x² + 12x − 7 and state its greatest y-value.
Problem 9 Complete the Square, Easy Case ★★★
Rewrite y = x² + 10x + 16 as y = a(x − h)² + k and read the turning point. Then find where the graph meets the x-axis.
Problem 10 Completing the Square, No Zeros ★★★
Rewrite y = x² − 8x + 19 as a square plus a constant. Explain why its graph stays above the x-axis.
Problem 11 Completing the Square, a = 2 ★★★
Complete the square for y = 2x² − 12x + 13 and name the turning point.
Problem 12 Graph from Zeros and Vertex ★★★
Sketch y = x² − 2x − 3 on the grid. Before plotting, find where it meets each axis and where it turns.
Problem 13 Vertex from Factored Form ★★★
Where does y = −2(x + 1)(x − 5) turn? Decide whether that point is a maximum or a minimum.
Problem 14 Compare Three Parabolas ★★★
Compare the graphs of y = x², y = 3x² and y = −0.5x². Which is narrowest, which opens down and which is widest?
Problem 15 Ball Launched from a Roof ★★★
From a rooftop, a water balloon is tossed upward. After t seconds its height is h(t) = −16t² + 48t + 64 feet. Find where it starts, how high it climbs and when it lands.
Problem 16 Largest Rectangular Pen ★★★
Dana encloses a rectangular dog run with 96 feet of fence. With width w, the enclosed area is A(w) = w(48 − w). Which width encloses the most ground, and how much is that?
Problem 17 Best Ticket Price ★★★
A drama club sells T-shirts at p dollars each and takes in R(p) = p(250 − 5p) dollars. Which price brings in the most money? How much is that, and at which prices does the club take in nothing?
Problem 18 Equation from Vertex and a Point ★★★
A parabola turns at (−1, 6) and also contains the point (2, −3). Express it as y = a(x − h)² + k and then in standard form.
Problem 19 Equation from Zeros and a Point ★★★
A parabola meets the x-axis at −2 and 4 and contains the point (0, −16). Give its equation in the form y = a(x − p)(x − q).
Problem 20 Compare Two Quadratic Functions ★★★
Let f(x) = x² − 6x + 11. A second function g has the table below.
| x | −1 | 0 | 1 | 2 | 3 |
|---|---|---|---|---|---|
| g(x) | 9 | 3 | 1 | 3 | 9 |
Which of the two functions dips lower, and at which x does each reach its lowest point?
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