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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.
To solve each inequality and graph its solution, you run the same four moves every time:
The second move is where most lost points live. Adding or subtracting never changes the symbol: becomes , and becomes , no drama either way.
Multiplying or dividing is different. Divide the true statement by and you get , still true. Divide it by and raw arithmetic gives , which is false. The only honest repair is to flip it to . 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.
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 means itself is not a solution — exactly what the strict inequality demands. A closed dot would mean the endpoint is included, as in .
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 , 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.
The graph of x > -2 on the number line: an open circle at -2 (endpoint excluded) and shading to the right.
Solve and graph: .
Answer: — 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.
Solve and graph: .
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).
Answer: — open circle at , 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.
A phone plan costs \24$0.15$45$ a month. How many texts can she send?
Set up her monthly total and keep it at or under the ceiling:
Answer: at most 140 texts per month, i.e. .
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.
Lina's solution t <= 140: a closed dot at 140 (endpoint included) and shading to the left.
Worksheet instructions are short, so every word carries weight:
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.
Solve and graph: .
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: — open circle at , shading to the left. Any two-step problem asking you to solve each inequality and graph its solution follows this exact script.
Solve each inequality and graph its solution: .
Solve and graph: .
A cycling tour charges a \12$5$47m$, solve it, and describe the graph of the solution.
Solve each inequality and graph its solution: .
Solve each inequality and graph its solution: .
Solve each inequality and graph its solution: .
Solve each inequality and graph its solution: .
Solve each inequality and graph its solution: .
Run this list every time you solve each inequality and graph its solution:
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.
Most lost points on this problem type come from one of four slips:
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.