Lesson 106: Solving Two-Step Equations Objective: Solve equations using two steps

Drill Rupesh earned some money mowing lawns one month. He put half of his money into savings. With the rest, he spent $15 on a new CD, $6 to see a movie, $3 on food, and he still had $24 left. How much money did Rupesh earn mowing lawns that month? In an intramural basketball game, Annie made 6 points more than Roberto. Roberto made half as many points as Charlie. Charlie made 3 more points than Darla. If Darla made 9 points, how many points did Annie make?

Objective - To solve equations involving two steps. 3x + 4 = 16 Hard way Easy way 3x + 4 = 16 3x + 4 = 16 - Undo Multiplication or Division first - Undo Addition or Subtraction first

Hard way - Undo Mult./ Div. first Easy way - Undo Add./ Subt. first 3x + 4 = 16 3x + 4 = 16 3 3 -4 -4 3x = 12 3x 4 16 + = 3 3 3 3 3 4 16 x = 4 x + = 3 3 4 4 - - 3 3 12 x = 3 x = 4

Rules for Transforming Equations 1) Goal: Isolate the variable on one side of the equation. ISOLATE 2) Always perform the same operation to both sides of an equation. BALANCE 3) To undo an operation, perform its opposite operation to both sides of the equation. INVERSE OPERATION

Solve the following equations.

Translate the sentence below and solve. 6) Five less than the quotient of x and 2 is 37.

Quick Draw for Points! Who is the best at showing their work? The text is TWO STEP EQUATIONS You will have 30-60 seconds for each problem. Are you ready to prove yourself?

Solve the following equations.

Translate the sentence below and solve. 5) Eight more than 3 times a number y is the same as 29.