Common Core: High School - Algebra

This subject covers the foundational concepts and skills of algebra as outlined in the Common Core standards for high school students.

Basic Concepts

Linear Equations and Inequalities

What Are Linear Equations?

Linear equations are equations where the variable (like \( x \)) appears only to the first power and graphs as a straight line. They usually look like \( ax + b = c \).

Solving Linear Equations

To solve, get the variable by itself using inverse operations (like subtracting what’s added, dividing what’s multiplied).

  • Step 1: Undo addition or subtraction.
  • Step 2: Undo multiplication or division.

What About Inequalities?

Inequalities work like equations, but instead of an \( = \), you use symbols like \( <, >, \leq, \geq \). They tell you if a value is less than, greater than, or equal to something.

When you solve inequalities and multiply or divide by a negative number, remember to flip the sign!

Why Does This Matter?

Linear equations and inequalities are everywhere—from planning budgets to tracking time.

Real-World Connections

  • Deciding if you have enough money for a purchase (\( x + 4 \leq 20 \))
  • Figuring out how long you can spend on homework if you want to finish before 8 PM.

Examples

  • Solve \( 2x + 3 = 7 \)\( x = 2 \)

  • Solve \( x - 5 > 10 \)\( x > 15 \)

In a Nutshell

Linear equations and inequalities help you solve for unknowns and compare values.