SAT Math

A comprehensive course to master all the mathematical concepts, skills, and strategies needed to succeed on the SAT exam.

Advanced Topics

Systems of Equations

What is a System of Equations?

A system is two or more equations with the same variables. The solution is where the equations overlap (the values that make all equations true).

Solving Methods

  • Substitution: Solve one equation for a variable, then substitute into the other.
  • Elimination: Add or subtract equations to eliminate a variable.
  • Graphing: Plot both and see where they cross.

Real-World Applications

Use systems to solve problems like finding prices of items, splitting costs, or comparing rates.

Pro Tips

  • Always check your solutions in both equations.
  • On the SAT, look for shortcuts—sometimes you can spot the answer by comparing equations.

Examples

  • Solving: \( x + y = 6 \), \( x - y = 2 \). Adding: \( 2x = 8 \rightarrow x = 4 \), \( y = 2 \)

  • Graphing the two equations and finding their intersection at (3, 1).

In a Nutshell

Systems help solve problems with more than one unknown by finding common solutions.