Quadratics Rectangle Worksheet: 20 Problems About Boxes That Fight Back
This quadratics rectangle worksheet takes patios, picture frames, walkways and one very stubborn field and turns them all into the same move: name a side x, write the other side in terms of x, multiply. Twenty problems in four parts, ten with a diagram, full answer key.
Published · Last updated · Every answer checked for accuracy before publishing · Free to print for classroom & home use
- Level
- Algebra I and Algebra II, grades 8–11
- Standards
- CCSS.MATH.CONTENT.HSA.CED.A.1 and HSA.REI.B.4.b
- Includes
- 20 problems in four parts, 10 with a diagram, three color-coded figures, and a full answer key
- Assumes
- Factoring and the quadratic formula already work — the picture is the new part
- Skills
- Naming an unknown, writing a second dimension in terms of it, expanding a product, rejecting an impossible root
- Time
- About 50 minutes, or one part at a time
- Format
- Read on this page or print the PDF, which has room to show work — no sign-up
Rectangle problems are the friendliest quadratics in the book, right up until somebody puts a frame around something. Then the width sneaks in twice per dimension, the student adds it once, and a perfectly good page of algebra goes in the bin. Draw the picture. Add the x to both ends. Everything after that is factoring you can already do.
- Draw the rectangle. Ugly is fine. Ugly is honestly preferred.
- Call one side x. Write every other side in terms of x.
- Length × width = area. Write it, then factor or use the quadratic formula.
- Delete the root that would give you a negative fence. Put a unit on the survivor.
Want the printable quadratics rectangle worksheet?
Eight pages: twenty problems with real space to show work, ten simple diagrams with the labels in a key beside them, and the full answer key. No sign-up, no email.
Download the PDF worksheetPDF · 8 pages · prints on letter paper
Parts A and B are one homework night. Part C is the one worth doing together, out loud, with a pencil on the picture. Part D is review the week before a test. Teachers: the parts split cleanly into four ten-minute stations, and the answer key prints on its own page so you can hold it back.
Four Setups in This Quadratics Rectangle Worksheet
Every rectangle problem you will ever be assigned is one of these. Textbooks just keep changing the nouns.
"Three more than the width." "Twice as long, less six."
Name the short side, build the long one, multiply.
Both dimensions grow or shrink by the same amount.
Two areas, one equation between them.
Frames, walkways, margins, mowed strips.
Width x on the left and the right. Hence 2x.
They hand you a fence length and an area.
Half the perimeter minus one side is the other side.
Two places. First, the border problem where somebody adds x instead of 2x — the algebra runs beautifully and the answer is wrong, which is the worst kind of wrong. Second, the last line, where a quadratic hands over two roots and the student boxes both. A frame cannot be −13 inches wide. Cross it out and write one short sentence saying why.
One Rectangle, Two Sides, One Equation
Start here. Every harder problem on this page is this one wearing a hat.
| Color | Part | What you write down |
|---|---|---|
| Red | Short sides | The one you name. Call it x |
| Blue | Long sides | x + 5, or 2x − 3, or whatever the sentence says |
| Pale fill | Inside | Area = red × blue. That is the equation |
| Gold | Corner | Where the two labeled sides meet. Start here |
If the factoring stalls rather than the setup, back up one step to solving quadratics by factoring, and keep completing the square in your pocket for the ones that refuse to factor.
The Frame Problem, Which Eats Everyone Once
A picture inside a frame. A garden inside a walkway. Print inside a margin. Same figure every time, and the same mistake every time.
| Color | Part | What you write down |
|---|---|---|
| Green | Inner | The picture, garden or print block. Sizes are given |
| Shaded | The band | The border. Uniform width x, all four sides |
| Gold | Outer | (L + 2x) by (W + 2x) |
| Purple | Arrows | x twice per dimension. This is the whole trap |
Cutting inward instead of building outward? Same figure, one sign flips: a strip mowed around the edge leaves a middle of (L − 2x) by (W − 2x). Problems 15 and 16 on this worksheet do exactly that, and both hand you a second root that is physically impossible — the sort of thing collected on the quadratics error analysis worksheet.
Before and After: Two Rectangles, One Sentence
"Each dimension is increased by 3 and the area goes up by 33." That is two rectangles and one equation linking them. Draw both. Nobody has ever solved one of these from memory.
| Color | Part | What you write down |
|---|---|---|
| Green | Solid | Before: x by (x + k) |
| Blue dashed | Outline | After: (x + a) by (x + k + a) |
| Pale fill | The gap | The change in area the problem quotes |
| Gold | Bracket | The amount added. Same on both dimensions |
Sentence In, Algebra Out
Five phrases cover almost everything. Learn the phrases and you have learned the chapter.
| The sentence says | You write | Why |
|---|---|---|
| "7 more than the width" | w and w + 7 | One unknown, one built from it |
| "six less than twice the width" | x and 2x − 6 | Double first, subtract second |
| "a border of uniform width" | L + 2x and W + 2x | The band is on both ends |
| "48 m of fencing" | x and 24 − x | Half the perimeter, minus one side |
| "25% more area" | new = 1.25 × old | Percent means multiply, not add |
(12 + x)(16 + x) = 396
x = 6
Added the border to one end only. It even factors cleanly, which is exactly why nobody notices.
(12 + 2x)(16 + 2x) = 396
x = 3 (x = −17 rejected)
Thirty seconds on a sketch buys you the 2. Then it factors.
Ten years of watching this unit and it is always the same shortlist. Nobody drew the picture. The border got added once instead of twice. Two different lengths both got called x. Or the algebra was perfect and the student answered with the width when the question asked for the area. Parts A through D below are ordered to walk into those in roughly that order, on purpose.
Quadratics Rectangle Worksheet: Twenty Practice Problems
Same twenty as the printable, same order, getting meaner as you go. Ten come with a diagram in the PDF — those are flagged below. Sketch the other ten yourself.
| Part | Problems |
|---|---|
| A · ONE RECTANGLE |
|
| B · BEFORE AND AFTER |
|
| C · FRAMES AND BORDERS |
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| D · THE ONES THAT BITE |
|
Part D borrows its shape from Regents-style modeling questions — if that is the exam in your future, the New York question bank at JMAP has years of them sorted by standard. Problem 17 will not factor, so it is quadratic-formula territory: see the quadratic formula worksheet and the discriminant and number of roots page. For projectiles, revenue and consecutive integers instead of rectangles, the quadratics word problems worksheet is the companion to this one.
Quadratics Rectangle Worksheet Answer Key
Part A · One rectangle
- 1
- A(w) = w(w + 5) = w² + 5w
- 2
- w(w + 6) = 91 → w² + 6w − 91 = 0 → (w + 13)(w − 7) = 0 → 7 m by 13 m
- 3
- x(2x − 3) = 54 → 2x² − 3x − 54 = 0 → (2x + 9)(x − 6) = 0 → x = 6 → 6 ft by 9 ft
- 4
- (2w)(w) = 60 → w² = 30 → w ≈ 5.5 ft, length ≈ 11.0 ft
- 5
- w(w + 25) = 7500 → w² + 25w − 7500 = 0 → (w − 75)(w + 100) = 0 → 75 yd by 100 yd
Part B · Before and after
- 6
- (x + 4)² = 9x² → 8x² − 8x − 16 = 0 → x² − x − 2 = 0 → (x − 2)(x + 1) = 0 → side 2 in
- 7
- (x + 2)(x + 8) = x(x + 6) + 48 → x² + 10x + 16 = x² + 6x + 48 → 4x = 32 → 8 ft by 14 ft
- 8
- (x − 2)(x + 8) = x(x + 10) − 76 → x² + 6x − 16 = x² + 10x − 76 → 15 cm by 25 cm
- 9
- (10 + x)(14 + x) = 192 → x² + 24x − 52 = 0 → (x + 26)(x − 2) = 0 → x = 2 ft
- 10
- 2s(s + 4) = 120 → s² + 4s − 60 = 0 → (s + 10)(s − 6) = 0 → square side 6 in
Part C · Frames and borders
- 11
- (10 + 2x)(14 + 2x) = 192 → x² + 12x − 13 = 0 → (x + 13)(x − 1) = 0 → 1 in
- 12
- (12 + 2x)(18 + 2x) = 315 → 4x² + 60x − 99 = 0 → (2x + 33)(2x − 3) = 0 → x = 1.5 m
- 13
- Mirror is 150 in², so the total is 300 in². (10 + 2x)(15 + 2x) = 300 → 2x² + 25x − 75 = 0 → (2x − 5)(x + 15) = 0 → 2.5 in
- 14
- (w − 2)(w + 1) = 40 → w² − w − 42 = 0 → (w − 7)(w + 6) = 0 → page is 7 in by 10 in
- 15
- (30 − 2x)(40 − 2x) = 600 → x² − 35x + 150 = 0 → (x − 5)(x − 30) = 0 → 5 ft. x = 30 would mow the lawn twice over
Part D · The ones that bite
- 16
- (100 − 2x)(120 − 2x) = 8000 → x² − 110x + 1000 = 0 → (x − 10)(x − 100) = 0 → 10 ft. x = 100 is rejected: the field is only 100 ft across, so a 100 ft ring on each side is impossible
- 17
- (150 + 2x)(200 + 2x) = 45,000 → x² + 175x − 3750 = 0 → x = (−175 + √45625) / 2 = (25√73 − 175) / 2 ≈ 19.3 ft
- 18
- l + w = 22, so w(22 − w) = 105 → w² − 22w + 105 = 0 → (w − 7)(w − 15) = 0 → 7 m by 15 m
- 19
- 50% more means multiply by 1.5, so 2x(x − 4) = 1.5x² → 0.5x² − 8x = 0 → x(x − 16) = 0 → original side 16 m, new garden 32 m by 12 m = 384 m²
- 20
- (8 + 2x)(10 + 2x) ≤ 143 → 4x² + 36x − 63 ≤ 0 → (2x + 21)(2x − 3) ≤ 0 → 0 < x ≤ 1.5 → widest strip 1.5 in
Every answer above was checked for accuracy before publishing, most recently on . If you spot an error, email burketutoringinfremont@outlook.com or text (510) 453-0350 and it will be corrected.
Common Questions
What is a quadratics rectangle problem?
Any situation where two sides of a rectangle depend on each other and you are given the area. Naming one side x forces the other side to be written in terms of x, and multiplying them gives a quadratic. Patios, gardens, picture frames, mowed lawns and printed pages are all the same problem.
Why is it 2x and not x for a frame?
Because the frame is on both sides. A 2 in frame around a 10 in photo makes the outside 14 in, not 12. Draw the picture and count the bands: two per dimension, every time. This single line is worth more marks than any other sentence on the page.
Which side should I call x?
Whichever one the sentence describes the other in terms of. "The length is 7 more than the width" means call the width x and the length x + 7. Choosing the other way round works too, it is just uglier for no reward.
Both answers are positive. Now what?
Check them against the picture, not the algebra. Problem 15 gives 5 and 30, and a 30 ft strip taken off each side of a 30 ft lawn removes 60 ft from a 30 ft width. Positive is not the same as possible.
Why do some problems give a perimeter instead of a second side?
Same information, wrapped differently. If the perimeter is 44, then length plus width is 22, so the sides are x and 22 − x. Halve first, then subtract. Problem 18 is exactly this.
What grade level is this quadratics rectangle worksheet?
Parts A and B sit squarely in Algebra I. Parts C and D show up in Algebra I too, then return in Algebra II and in the SAT's harder math module wearing slightly different clothes.
Can I use this in my classroom?
Print it, copy it, project it, hand it out. No sign-up and no attribution required, though a link back is always welcome.
More Quadratics Practice
Rectangle problems assume the solving already works. When a part keeps stalling, the trouble is almost always upstream of the picture.
- Solving
- Solving by factoring · the quadratic formula · completing the square · the discriminant
- Maximum area
- Largest-pen questions are vertex questions: vertex and axis of symmetry · graphing quadratic functions · writing the equation from a graph · quadratic transformations
- Other stories
- Projectiles, revenue and consecutive integers: quadratics word problems. Curved reflectors instead of flat rectangles: focus and directrix word problems. Not sure the model is even quadratic? Compare the function families
- Keeping it warm
- Quadratics spiral review · quadratics error analysis
- Checking work
- Sketch the area function in GeoGebra or push the roots through MathPapa. Neither will read the sentence for you, which is the actual difficulty
Standards and References
These problems were written against the following standards and checked against the following references.
- Building an equation from a described geometric situation is CCSS.MATH.CONTENT.HSA.CED.A.1. Standard text: Common Core, High School Algebra: Creating Equations.
- Solving the resulting equation by factoring, completing the square or the formula is HSA.REI.B.4.b.
- Exam-style parallels for Parts C and D: JMAP, which sorts released New York Regents questions by standard, including the geometric applications of quadratics set.
- Classic rectangle, frame and spiral-mowing problems in an openly licensed text: LibreTexts Mathematics, which hosts Tyler Wallace's Beginning and Intermediate Algebra under CC BY 3.0.
- Position on modeling and problem representation in algebra: National Council of Teachers of Mathematics.
- Plain-English refreshers for students: MathBits Notebook, Cuemath on area of a rectangle, and eMathHelp for a stepped second opinion.
- Reuse: the problems on this page are original to Burke Tutoring and free to print, copy or project. The classic problem types they follow — frames, borders and spiral mowing — appear in openly licensed algebra texts distributed under CC BY 3.0.
- Answer verification: every solution was substituted back into its own equation, checked against the picture for impossible roots, and cross-checked with an independent area calculator and GeoGebra.
About the Author
Page Updates
- — quadratics rectangle worksheet published with twenty problems in four parts, three color-coded figures, the eight-page printable PDF and the full answer key. — added quadratics hub page link.
Frame and border problems turn up in Algebra I at every high school around here — Irvington, American, Mission San Jose, Washington and Kennedy in Fremont, Newark Memorial, and James Logan in Union City. They are quick to fix in person, because most of the fix is sitting next to a student while they draw the picture. Burke Tutoring offers in-home algebra tutoring in Fremont, Newark, and Union City. Call (510) 453-0350.
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