---
title: "Modulus Functions and Modulus Equations"
description: "Read the modulus as distance from zero, sketch the V-shaped graph it produces, and solve equations and inequalities that contain one."
canonical: https://lightmysky.com/learn/mathematics/modulus-functions-and-modulus-equations-mt__W-aDpT5jz
source: https://lightmysky.com/learn/mathematics/modulus-functions-and-modulus-equations-mt__W-aDpT5jz.md
retrieved: 2026-09-12
---

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# Modulus Functions and Modulus Equations

Read the modulus as distance from zero, sketch the V-shaped graph it produces, and solve equations and inequalities that contain one.

Subject: Mathematics · Area: Algebra · Ages 16 to 17
Page: https://lightmysky.com/learn/mathematics/modulus-functions-and-modulus-equations-mt__W-aDpT5jz

## Ready when they can

- Sketch y equals the modulus of a linear expression and mark where the graph turns
- Solve a modulus equation by splitting into the two cases and rejecting solutions that fail the original
- Solve a modulus inequality and write the answer as an interval or a union of intervals

## Lesson: Taming the modulus

Read the bars as stretch from zero. The graph makes a V whose bend sits where the inner line hits zero. For y shaped by x minus 3, the bend lands at (3, 0).

**Example.** Split each equation into twin cases, one per sign. For bars round 2x minus 4 set to 6, work 2x minus 4 as 6 and as minus 6. The roots are 5 and minus 1.

Each root must face the first equation. Some guests fail at the door, as in bars round x set to x plus 2, where 1 breaks the check and just minus 1 stays. Keep just the ones that pass.

**Tip.** Gaps use stretch sense too. Bars round x minus 1 under 4 means within 4 of 1, so minus 3 through 5. Past marks split outward with OR: bars round x minus 2 past 5 means x past 7 or x under minus 3.

**Recap.** Split by sign, test each guest in the first equation, and read gaps as near or far.

## Practice

17 questions on this page, each with its working shown.

## Needs first

- [Transformations of Graphs](https://lightmysky.com/learn/mathematics/transformations-of-graphs-mt_691_c-7Z5M)
- [Solving Linear Inequalities and Solution Sets](https://lightmysky.com/learn/mathematics/solving-linear-inequalities-and-solution-sets-mt_QkG3Cw5VgM)
- [Absolute value as distance from zero](https://lightmysky.com/learn/mathematics/absolute-value-as-distance-from-zero-mt_RWUY7_IXvw)
- [Function Notation and Evaluating Functions](https://lightmysky.com/learn/mathematics/function-notation-and-evaluating-functions-mt_YWKWzHK_6Z)

## Opens up

- [Rational Functions, Asymptotes and Curve Sketching](https://lightmysky.com/learn/mathematics/rational-functions-asymptotes-and-curve-sketching-mt_U-f9YTNb2o)
