Systems of Linear Equations
Solve systems using substitution, elimination, and graphing.
Practice Problems
y = 2x + 1; 3x + y = 11
2x + 3y = 12; 4x - 3y = 6
Pro Tips & Shortcuts
SAT Tip: On the SAT, you'll use substitution or elimination methods to solve systems efficiently.
SAT Tip: Use substitution when one equation is already solved for a variable or can be easily solved.
SAT Tip: Use elimination when coefficients are already aligned or can be easily made to match.
SAT Tip: When one equation is already in y = mx + b form, substitution is usually fastest.
SAT Tip: When coefficients are already opposites, elimination is the fastest method.
If coefficients of one variable are opposites, use elimination immediately.
Choose the equation and variable that's easiest to isolate.
Look for coefficients that are opposites or multiples of each other.
Always check your solution in both original equations.
Adding eliminates variables with opposite coefficients; subtracting eliminates same coefficients.