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Solve Each Inequality and Graph Its Solution

A speed limit sign never says "drive exactly 55" — it says 55 and under, and every speed in that whole stretch is legal. An inequality answer works the same way: not one number, but an entire ray. When you solve each inequality and graph its solution, the algebra turns into that picture. This page runs the routine on one-step, multi-step, and word problems alike.

How to Solve Each Inequality and Graph Its Solution

To solve each inequality and graph its solution, you run the same four moves every time:

  1. Solve it like an equation. Undo operations on both sides — add, subtract, multiply, divide — until the variable stands alone.
  2. Watch the sign. If you multiply or divide both sides by a negative number, reverse the inequality symbol.
  3. Mark the endpoint. Draw an open circle for << or >>, and a closed dot for ≤\leq or ≥\geq.
  4. Shade the direction. Pick one easy number on each side of the endpoint and test it in the original inequality; shade the side that works.

The second move is where most lost points live. Adding or subtracting never changes the symbol: x+3>5x + 3 > 5 becomes x>2x > 2, and x−7≤1x - 7 \leq 1 becomes x≤8x \leq 8, no drama either way.

Multiplying or dividing is different. Divide the true statement 10>610 > 6 by 22 and you get 5>35 > 3, still true. Divide it by −2-2 and raw arithmetic gives −5>−3-5 > -3, which is false. The only honest repair is to flip it to −5<−3-5 < -3. That is why we solve each inequality and graph its solution with the flip rule in hand: the symbol must keep saying which side is bigger.

One word deserves its own note. Each is a counting word: every listed inequality gets its own full solution and its own graph. A worksheet prompt means committing to the whole list.

Reading the Graph: Open Points, Closed Dots, and Direction

A number line graph answers two questions at a glance: where does the solution start, and which way does it run?

The endpoint tells you where. An open circle at −2-2 means −2-2 itself is not a solution — exactly what the strict inequality x>−2x > -2 demands. A closed dot would mean the endpoint is included, as in x≤3x \leq 3.

The shading tells you which way. Shading to the right collects every number bigger than the endpoint; shading to the left collects every number smaller. After you solve the inequality and graph, read the picture back as a sentence: "everything to the right of −2-2, endpoint excluded." Ten seconds of testing one shaded value catches almost every direction mistake.

When you solve each inequality and graph its solution, the picture and the algebra must agree on three details at once.

The endpoint style matches the symbol, the shading matches the direction, and nothing else on the line gets drawn.

Practicing how to solve each inequality and graph its solution really means auditing those three details every single time. Graph-first readers can also solve each inequality and graph its solution by testing points on the drawing itself.

-4-2024x > -2

The graph of x > -2 on the number line: an open circle at -2 (endpoint excluded) and shading to the right.

Worked Example 1: One Step, No Surprises

Solve and graph: y−4≥6y - 4 \geq 6.

  • Add 4 to both sides: y≥10y \geq 10. Adding a positive number never flips the sign.
  • Endpoint: a closed dot at 10, because ≥\geq includes 10 itself.
  • Direction: shade right, since every number above 10 works. Check one: 11−4=7≥611 - 4 = 7 \geq 6. ✓

Answer: y≥10y \geq 10 — closed dot at 10, shading to the right.

One step, one flip-check that passed, one graph: that is the whole routine when you solve each inequality and graph its solution at its simplest. Log the pattern now, because Example 2 will stress-test it. Drills this simple are where you rehearse how to solve each inequality and graph its solution before harder ones arrive. One rep like this is enough preparation to solve each inequality and graph its solution with confidence.

Worked Example 2: Dividing by a Negative Flips the Sign

Solve and graph: −6v>48-6v > 48.

  • Divide both sides by −6-6. Dividing by a negative reverses the symbol: v<−8v < -8.

Textbooks have warned about exactly this step for over a century. An old analytic geometry text puts it in one line: "changing signs throughout an inequality reverses the inequality sign" (Smith & Gale, 1904).

  • Endpoint: an open circle at −8-8, because the strict << excludes it.
  • Direction: shade left. Check a shaded value: −6×(−9)=54>48-6 \times (-9) = 54 > 48. ✓

Answer: v<−8v < -8 — open circle at −8-8, shading to the left.

This example is the classic reason students drop points when they solve each inequality and graph its solution under time pressure. The algebra was one division; the only possible error was the flip, and it is worth a whole letter grade. Whenever you solve each inequality and graph its solution with a negative divisor, say the flip out loud as you write it. The graph makes the flip visible: solve each inequality and graph its solution, and the arrow direction confirms the reversed symbol.

Worked Example 3: From a Word Problem to the Graph

A phone plan costs \24permonthplusper month plus$0.15pertext.Linacanspendatmostper text. Lina can spend at most$45$ a month. How many texts can she send?

Set up her monthly total and keep it at or under the ceiling:

24+0.15t≤4524 + 0.15t \leq 45

  • Subtract 24 from both sides: 0.15t≤210.15t \leq 21.
  • Divide by 0.150.15 (positive, so no flip): t≤140t \leq 140.
  • Graph: a closed dot at 140 with shading to the left — 140 texts are allowed, and so is every smaller number.

Answer: at most 140 texts per month, i.e. t≤140t \leq 140.

Budget problems like this one show why it pays to solve each inequality and graph its solution instead of guessing one safe number. The graph displays every acceptable value at once, ceiling included. The same routine lets you solve each inequality and graph its solution for any budget, data plan, or paycheck cap. Money limits are the natural place to solve each inequality and graph its solution before spending a single dollar.

120130140150t <= 140

Lina's solution t <= 140: a closed dot at 140 (endpoint included) and shading to the left.

What "Each" Means: Reading the Instruction Word by Word

Worksheet instructions are short, so every word carries weight:

  • Solve — do the algebra until the variable stands alone.
  • Each — every listed item is a separate problem with a separate answer.
  • Graph — the answer is not finished until it lives on a number line.
  • Its — each solution belongs to its own inequality. Never reuse one graph for the whole list.

Read that way, to solve each inequality and graph its solution is a four-part promise, and graders check all four parts. A sheet headed "solve each inequality and graph its solution" is announcing its rubric in advance. Graders expect you to solve each inequality and graph its solution once per listed item — no more, no less.

Worked Example 4: Two Steps, Variable Terms First, Then a Flip

Solve and graph: 7−3x>167 - 3x > 16.

  • Subtract 7 from both sides: −3x>9-3x > 9. Subtraction never flips anything.
  • Divide by −3-3 and flip: x<−3x < -3.
  • Endpoint: an open circle at −3-3, because the flipped strict << still excludes it.
  • Direction: shade left. Check: 7−3(−4)=19>167 - 3(-4) = 19 > 16. ✓

Two moves instead of one, but the audit is identical: did a negative divisor appear, and did the symbol turn? Ask that every time you solve each inequality and graph its solution, and the flip stops being forgettable.

Answer: x<−3x < -3 — open circle at −3-3, shading to the left. Any two-step problem asking you to solve each inequality and graph its solution follows this exact script.

Problem 1

Solve each inequality and graph its solution: x+7≤3x + 7 \leq 3.

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Problem 2

Solve and graph: −4x>20-4x > 20.

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Problem 3

A cycling tour charges a \12helmetrentalplushelmet rental plus$5perguidedmile.Mateo′sbudgetforthetourisatmostper guided mile. Mateo's budget for the tour is at most$47.Writeaninequalityforthenumberofmiles. Write an inequality for the number of miles m$, solve it, and describe the graph of the solution.

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Problem 4

Solve each inequality and graph its solution: 2x<102x < 10.

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Problem 5

Solve each inequality and graph its solution: 3−2w≥93 - 2w \geq 9.

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Problem 6

Solve each inequality and graph its solution: x4>3\frac{x}{4} > 3.

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Problem 7

Solve each inequality and graph its solution: x−8>−2x - 8 > -2.

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Problem 8

Solve each inequality and graph its solution: −5y≤25-5y \leq 25.

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A Four-Point Check Before You Box the Answer

Run this list every time you solve each inequality and graph its solution:

  1. Algebra check: the endpoint substituted into the original inequality comes out true or exactly equal.
  2. Flip check: any step that multiplied or divided by a negative has a reversed symbol.
  3. Endpoint check: strict <<, >> get open circles; ≤\leq, ≥\geq get closed dots.
  4. Direction check: one test value from the shaded side satisfies the original.

Whether you solve each inequality and graph its solution in one step or in four, the list never changes. Make it a reflex and you will solve each inequality and graph its solution correctly on the first pass.

Common Mistakes When You Solve Inequalities and Graph Solutions

Most lost points on this problem type come from one of four slips:

  1. Forgetting the flip. Dividing by a negative without reversing the symbol turns −6v>48-6v > 48 into the wrong answer v>−8v > -8. The moment your last step divides by a negative, reverse the sign.
  2. Drawing the direction backwards. The shading runs toward the values that work, not toward the bigger numbers by default. v<−8v < -8 shades left, even though left usually means "smaller than everything you solved for."
  3. Mixing up open and closed endpoints. A closed dot drawn where an open circle belongs (or the reverse) changes the answer by exactly one, often-graded point: strict <,><, > take open circles; ≤,≥\leq, \geq take closed dots.
  4. Answering only the first item. When the sheet says "each", every listed inequality needs its own solution and its own graph — half the list means half the credit.

Notice that three of the four slips happen after the algebra is already done. Slow, audited work is how strong students solve each inequality and graph its solution without any of these slips.

Frequently asked questions

1

How do you solve the inequality and graph the solution on a number line?

Isolate the variable with the same moves you would use on an equation, reversing the sign only if you multiply or divide by a negative. Then mark the endpoint — open circle for $<$ or $>$, closed dot for $\leq$ or $\geq$ — and shade toward the side that makes the inequality true. In short: to solve each inequality and graph its solution, you solve, flip-check, mark, shade.

2

When you solve an inequality and graph the solution, why is the endpoint sometimes open and sometimes closed?

It depends on the symbol. Strict inequalities ($<$, $>$) do not include the endpoint, so it gets an open circle. Inclusive inequalities ($\leq$, $\geq$) do include it, so it gets a closed dot. If checking the endpoint value in the original inequality gives a true statement, the dot is closed. The test costs two seconds and settles the open-versus-closed question every time you solve each inequality and graph its solution on paper.

3

How to solve each inequality and graph its solution when a worksheet lists several at once?

Treat every item as its own problem: full solution, endpoint, direction. The word "each" is graded — answer only the first one and the rest are marked wrong even if that first graph is perfect. One item, one full pass — that is how you solve each inequality and graph its solution without losing points.

4

How to solve inequality and graph its solution without forgetting to flip the sign?

Flip only when you multiply or divide both sides by a negative number — never for addition or subtraction. If flipping trips you up, move the variable terms first so the variable ends up with a positive coefficient. Plain division then finishes the problem with no flip at all. That trick makes the flip nearly impossible to forget when you solve each inequality and graph its solution under exam pressure.

5

Is solving the inequality by graphing different from solving it with algebra?

Yes. When a problem says "solve the inequality by graphing", you draw the boundary value on a number line and read off which side works. That is great for checking, but the endpoint often stays approximate. Solving with algebra gives the exact endpoint first; the graph then displays it. Either way, you still have to solve each inequality and graph its solution before the answer counts as finished.

6

Do I also need interval notation for my answer?

Often yes in algebra courses. The same solution can be written three ways. You can write an inequality ($x > -2$), draw a number line graph, or use interval notation $(-2, \infty)$. A parenthesis marks an open endpoint, and a bracket marks a closed one. Interval or picture, both forms answer the same request to solve each inequality and graph its solution in writing.

7

Why does the instruction say solve each inequality and graph its solution instead of just solve?

Because the word "each" is part of the grade. The solver wants the algebra for every listed item, plus a number line for every listed item. One merged answer, or one graph reused twice, loses exactly the points that "each" was put there to protect. Rubrics score it that way because to solve each inequality and graph its solution is four separate jobs per item.

8

After I solve each inequality and graph its solution, how do I confirm the shading is on the correct side?

Test one number from inside the shaded region. Substitute it into the original inequality. A true statement means the shading is correct; a false one means only the picture needs repair, and the algebra is probably fine. That second look closes the loop on your attempt to solve each inequality and graph its solution.

9

Can you solve each inequality and graph its solution without a number line at all?

You can state the answer as an inequality or in interval notation, but the instruction explicitly asks for the graph. The number line is the deliverable: it shows the endpoint style and the direction that algebra alone leaves implicit. Skip it and the answer is incomplete.

10

Is there a difference between paper work and a calculator when you solve each inequality and graph its solution for homework?

The algebra is identical. A solver returns the boundary and the interval, and you still translate that into an open or closed point with shading. Knowing how to solve each inequality and graph its solution yourself is what lets you catch a typo in the machine's input. The graph is what it means to solve each inequality and graph its solution completely.

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