Solving Two-Step Equations

Solving Two-Step Equations

Algebra Tiles

Variable Zero Pairs

Zero Pairs

Example 1

Check our work -5 = 2x + 1 -5 = 2(-3) + 1 -5 = -6 + 1 -5 = -5

Example 2

Let’s check our work: 3x – 2 = 4 3(2) – 2 = 4 6 – 2 = 4 4 = 4

Example 3

Let’s check our work: 2x + 1 = 5 2(2) +1 = 5 4 +1 = 5 5 = 5

Steps for solving • Get the variable term by itself. • In other words, do the addition/subtraction first. • Isolate the variable. • In other words, do the multiplication/ division last. *****HINT! Whatever you do to one side of the equation you MUST do to the other side!

Example • 2x + 3 = 7 *Get the variable term alone* -3 -3 “undo” addition by subtraction 2 x = 4 *Isolate the variable* 2 2 “undo” multiplication by division x = 2

Solve + 4 = 9 + 4 = 9 - 4 - 4 (Subt. 4 from both sides)  3 = 5  3 (Mult. by 3 on both sides) x = 15 = 5

Try These Problems x = 7 • 3x – 5 = 16 • 12 = 13 + • 16 = 4n + 4 • – 6 = 4 y = -4 n = 3 n = 20

Time to Review! • Keep the equation balanced. • Use inverse operations to “undo” • Follow the rules: • Undo Addition or Subtaction • Undo Multiplication or Division

Practice Worksheet

Solving Two-Step Equations