6.AT.9 Lesson 8-4-part2 Apply Day · Set B
MASTERY CHECK
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8.4 · Part II

Second Practice Form · Independent Application and Spiral Review

Write Inequalities · Inequality

Interactive Workbench & Models →
Name: Date: Period: Learning Goal:
■ ADVANCED CONCEPT ANCHOR: 8.4 · Part II
1Writing & Representing Inequalities
2The Structural Procedure
  1. 'At least', 'minimum', 'no less than' translate to ≥ (greater than or equal to)
  2. 'At most', 'maximum', 'no more than' translate to ≤ (less than or equal to)
  3. 'More than' is >; 'Fewer than' / 'Less than' is <
3Mathematical Word Bank
  • Write Inequalities (Escribir desigualdades) — Represent a range of possible values with <, >, ≤, or ≥.
  • Inequality (Desigualdad) — A math sentence that compares two sides with <, >, ≤, or ≥.
  • Greater than (Mayor que) — The > sign, showing one number is bigger.
  • Less than (Menor que) — The < sign, showing one number is smaller.
  • At least / At most (Al menos / A lo más) — 'At least' means ≥. 'At most' means ≤.
  • Variable (Variable) — A letter that stands for a number that is unknown or can change.
4Watch out
  • A common mistake in Write Inequalities is using a strict symbol (> or <) for a phrase that actually includes the boundary value. For 'the suspect is at least 18 years old,' students often write a > 18 instead of the correct a ≥ 18 — this wrongly excludes 18 itself, even though 'at least 18' means 18 counts as a match. The same error happens in reverse with 'at most': for 'the getaway bag holds at most 12 items,' students write n < 12 instead of n ≤ 12. Always ask: does the key phrase include the number ('at least,' 'at most,' 'no more than,' 'no fewer than' → use ≥ or ≤) or exclude it ('more than,' 'fewer than' → use > or <)?
  1. 1 MULTIPLE CHOICE

    A fair ride requires each rider to be at least 48 inches tall. Let h be a rider's height in inches. Which inequality represents the heights that are allowed to ride?

    1. Ah ≥ 48
    2. Bh > 48
    3. Ch ≤ 48
    4. Dh < 48
    ✏️ Workspace & Solution Steps
  2. 2 MULTIPLE CHOICE

    Which inequality represents: 'The temperature is less than 40 degrees'?

    1. At < 40
    2. Bt > 40
    3. Ct ≤ 40
    4. Dt = 40
    ✏️ Workspace & Solution Steps
  3. 3 MULTIPLE CHOICE

    Which inequality represents: 'You must be at least 48 inches tall to ride'?

    1. Ah ≥ 48
    2. Bh > 48
    3. Ch < 48
    4. Dh ≤ 48
    ✏️ Workspace & Solution Steps
  4. 4 MULTIPLE CHOICE

    Which inequality represents: 'A store can hold no more than 75 people'?

    1. Ap ≤ 75
    2. Bp < 75
    3. Cp ≥ 75
    4. Dp > 75
    ✏️ Workspace & Solution Steps
📐 CER MATHEMATICAL PROOF MATRIX (CER 2.0) SMP.3 / Proof & Justification

Writing Task: Justify why your mathematical solution is accurate and complete.

C Claim
State your direct mathematical answer/claim with units.
E Evidence
Cite exact numbers, calculations, dimensions, or graph data.
R Reasoning
Explain the mathematical theorem, property, or definition connecting evidence to claim.
Student Mastery Self-Assessment:
1 · Need More Support
2 · Getting Closer
3 · Got It / Solid
4 · Master / Can Teach It