ACCUPLACER Elementary Algebra

ACCUPLACER Elementary Algebra focuses on assessing and enhancing foundational algebra skills essential for success in higher-level mathematics.

Advanced Topics

Solving and Graphing Linear Inequalities

What Are Linear Inequalities?

Linear inequalities look like equations but use symbols like \( <, >, \leq, \geq \) instead of \( = \).

How to Solve

  • Treat them almost like equations, but remember:
    • When you multiply or divide both sides by a negative number, flip the inequality sign!
  • The solution is often a range of numbers.

Graphing Solutions

  • Use a number line.
  • Open circle for \( < \) or \( > \), closed circle for \( \leq \) or \( \geq \).
  • Shade the region representing all possible solutions.

Everyday Uses

Inequalities can show which options are within your budget, or how much time you have left before a deadline.

Key Formula

\[ax + b < c\]

Examples

  • Solve \( x - 4 > 2 \) gives \( x > 6 \); graph with an open circle at 6 and shade right.

  • Solve \( 2y + 3 \leq 7 \) gives \( y \leq 2 \); graph with a closed circle at 2 and shade left.

In a Nutshell

Solve inequalities and show solutions on a number line.

Key Terms

Inequality
A mathematical sentence that shows the relationship between quantities that are not equal.
Number Line
A line on which numbers are marked at intervals, used to illustrate solutions.