Solve the inequality: \(2x+5\geq13\)
- \(x\geq3\)
- \(x\geq4\)
- \(x\leq4\)
- \(x\geq9\)
Testinar Grade 7 math
Writing and Solving Inequalities
Students will build Grade 7 mastery of writing and solving inequalities using models, equations, and test-style reasoning.
CH05-05
Equations and Inequalities
- Name
- Date
- Score
- ____ / 8
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Which inequality represents "a number plus 8 is less than 15"?
- \(x+8<15\)
- \(x+8>15\)
- \(x-8<15\)
- \(8x<15\)
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Solve: \(x+7<12\)
- \(x<5\)
- \(x>5\)
- \(x\leq5\)
- \(x<19\)
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Solve: \(\frac{x}{3}\geq2\)
- \(x\geq\frac{2}{3}\)
- \(x\leq6\)
- \(x\geq6\)
- \(x\geq2\)
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Solve: \(4x<20\)
- \(x>5\)
- \(x<5\)
- \(x\geq5\)
- \(x<80\)
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Solve: \(3x-4\leq11\)
- \(x\geq5\)
- \(x\leq5\)
- \(x>5\)
- \(x\leq15\)
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Solve: \(-2x+3<9\)
- \(x>-3\)
- \(x<-3\)
- \(x<6\)
- \(x\geq3\)
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Maria earns $12 per hour. How many hours must she work to earn at least $144?
- \(h<12\)
- \(h\geq12\)
- \(h\leq144\)
- \(h>12\)
Answer key and explanations
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B. \(x\geq4\)
Subtract \(5\): \(2x\geq8\). Divide by \(2\): \(x\geq4\).
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A. \(x+8<15\)
"A number plus 8" translates to \(x+8\), and "is less than" translates to \(<\).
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A. \(x<5\)
Subtract \(7\) from both sides: \(x<12-7=5\).
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C. \(x\geq6\)
Multiply both sides by \(3\): \(x\geq6\). The inequality sign stays the same because we multiply by a positive.
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B. \(x<5\)
Divide both sides by \(4\): \(x<\frac{20}{4}=5\).
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B. \(x\leq5\)
Add \(4\): \(3x\leq15\). Divide by \(3\): \(x\leq5\).
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A. \(x>-3\)
Subtract \(3\): \(-2x<6\). Divide by \(-2\) and flip the sign: \(x>-3\).
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B. \(h\geq12\)
"At least $144" means \(\geq\). Set up: \(12h\geq144\). Divide by \(12\): \(h\geq12\).
