8.7 · Part II
Supported Application · Guided Entry to Today's Problem
Equations and Inequalities Problem Solving · Model
- Define the variable and units in the scenario
- Look for keywords: 'equals/is' (=) vs 'at least/limit' (≥, ≤, >, <)
- Write the algebraic model, solve with inverse operations, and check in context
- Equations and Inequalities Problem Solving (Resolución de problemas con ecuaciones y desigualdades) — Use an equation for one exact value or an inequality for a range of values in a real situation.
- Model (Modelar) — To show a real-life situation with an equation or inequality.
- Equation (Ecuación) — A math sentence with an equal sign showing both sides are the same.
- Inequality (Desigualdad) — A math sentence that compares two sides with <, >, ≤, or ≥.
- Reasonableness (Razonabilidad) — Checking if your answer makes sense.
- Variable (Variable) — A letter that stands for a number that is unknown or can change.
- A common mistake in Equations and Inequalities Problem Solving is matching the wrong model to a key phrase. For 'the getaway car held no more than 6 bags,' students often write the equation b = 6 instead of the inequality b ≤ 6, because they see one number and assume it must be exact. The same mistake happens in reverse: for 'the reward split equally among 5 people gave each $40,' students sometimes write the inequality 5p ≥ 40 instead of the equation 5p = 40, because 'split equally' sounds like it could mean a range. Before you submit, ask: does this phrase give one exact value (equation, =) or a limit/range (inequality, <, >, ≤, ≥)?
-
1 MULTIPLE CHOICE
A bus can carry at most 48 passengers. There are already 31 on board. Which inequality shows how many more can board?
- A31 + p ≤ 48
- B31 + p > 48
- C31 + p = 48
- Dp − 31 ≤ 48
✏️ Workspace & Solution Steps -
2 MULTIPLE CHOICE
(Lesson 8.4) Which inequality represents: 'The temperature is less than 40 degrees'?
- At < 40
- Bt > 40
- Ct ≤ 40
- Dt = 40
✏️ Workspace & Solution Steps -
3 MULTIPLE CHOICE
(Lesson 8.4) Which inequality represents: 'You must be at least 48 inches tall to ride'?
- Ah ≥ 48
- Bh > 48
- Ch < 48
- Dh ≤ 48
✏️ Workspace & Solution Steps
Writing Task: Justify why your mathematical solution is accurate and complete.
8.7 · Part II
On-Level Application · Standard Rigor
Equations and Inequalities Problem Solving · Model
- Define the variable and units in the scenario
- Look for keywords: 'equals/is' (=) vs 'at least/limit' (≥, ≤, >, <)
- Write the algebraic model, solve with inverse operations, and check in context
- Equations and Inequalities Problem Solving (Resolución de problemas con ecuaciones y desigualdades) — Use an equation for one exact value or an inequality for a range of values in a real situation.
- Model (Modelar) — To show a real-life situation with an equation or inequality.
- Equation (Ecuación) — A math sentence with an equal sign showing both sides are the same.
- Inequality (Desigualdad) — A math sentence that compares two sides with <, >, ≤, or ≥.
- Reasonableness (Razonabilidad) — Checking if your answer makes sense.
- Variable (Variable) — A letter that stands for a number that is unknown or can change.
- A common mistake in Equations and Inequalities Problem Solving is matching the wrong model to a key phrase. For 'the getaway car held no more than 6 bags,' students often write the equation b = 6 instead of the inequality b ≤ 6, because they see one number and assume it must be exact. The same mistake happens in reverse: for 'the reward split equally among 5 people gave each $40,' students sometimes write the inequality 5p ≥ 40 instead of the equation 5p = 40, because 'split equally' sounds like it could mean a range. Before you submit, ask: does this phrase give one exact value (equation, =) or a limit/range (inequality, <, >, ≤, ≥)?
-
1 MULTIPLE CHOICE
A student solved 4n = 52 and got n = 13. Is the answer reasonable if n represents the number of notebooks in a box?
- AYes — 13 notebooks per box is reasonable
- BNo — 13 is too many notebooks
- CNo — the answer should be 48
- DYes — but only if n is a fraction
✏️ Workspace & Solution Steps -
2 MULTIPLE CHOICE
Room 2: The vault keypad clue reads, 'A number of stolen coins plus 6 equals 14.' Solve x + 6 = 14 to find the code x.
- Ax = 8
- Bx = 20
- Cx = 6
- Dx = 2
✏️ Workspace & Solution Steps -
3 MULTIPLE CHOICE
Room 3: A sign warns, 'The safe holds at most 20 gold bars.' Which inequality models the number of bars x?
- Ax ≤ 20
- Bx ≥ 20
- Cx > 20
- Dx = 20
✏️ Workspace & Solution Steps
Writing Task: Justify why your mathematical solution is accurate and complete.
8.7 · Part II
Extension & Non-Routine Application
Equations and Inequalities Problem Solving · Model
- Define the variable and units in the scenario
- Look for keywords: 'equals/is' (=) vs 'at least/limit' (≥, ≤, >, <)
- Write the algebraic model, solve with inverse operations, and check in context
- Equations and Inequalities Problem Solving (Resolución de problemas con ecuaciones y desigualdades) — Use an equation for one exact value or an inequality for a range of values in a real situation.
- Model (Modelar) — To show a real-life situation with an equation or inequality.
- Equation (Ecuación) — A math sentence with an equal sign showing both sides are the same.
- Inequality (Desigualdad) — A math sentence that compares two sides with <, >, ≤, or ≥.
- Reasonableness (Razonabilidad) — Checking if your answer makes sense.
- Variable (Variable) — A letter that stands for a number that is unknown or can change.
- A common mistake in Equations and Inequalities Problem Solving is matching the wrong model to a key phrase. For 'the getaway car held no more than 6 bags,' students often write the equation b = 6 instead of the inequality b ≤ 6, because they see one number and assume it must be exact. The same mistake happens in reverse: for 'the reward split equally among 5 people gave each $40,' students sometimes write the inequality 5p ≥ 40 instead of the equation 5p = 40, because 'split equally' sounds like it could mean a range. Before you submit, ask: does this phrase give one exact value (equation, =) or a limit/range (inequality, <, >, ≤, ≥)?
-
1 MULTIPLE CHOICE
A school van can carry at most 14 passengers. There are already 9 passengers on board. Let p be the number of additional passengers who can get on. Which inequality models this situation?
- A9 + p ≤ 14
- B9 + p ≥ 14
- C9 + p < 14
- Dp − 9 ≤ 14
✏️ Workspace & Solution Steps
Writing Task: Justify why your mathematical solution is accurate and complete.