Solving Systems of Linear Equations

The Substitution Method

Step 1: Solve for the first variable:

y=3; 2x+y=15; 2x+(3x)=15; 2x+3x=15; 5x=15; 5x/5=15/5; x=3

Step 2: Solve for the second variable:

y=3x; y=3(3); y=9

Step 3: Write your solution:

(3,9)

Step 4: Check your solution:

y=3x; 9=3(3); 9=9