Objective The student will be able to: solve equations using multiplication and division. Designed by Skip Tyler, Varina High School 1) Solve. -5t = 60 To get the variable by itself, which number needs to be moved? -5 To move the -5, you have to do the opposite operation. What operation will we use? division 1. 2. 3. 4. 1) Solve -5t = 60 -5 -5 Draw “the river” to t = -12 separate the equation into 2 sides Divide both sides by -5 Simplify Check your answer -5(-12) = 60 1. 2. 3. 4. 2) Solve 15 = 6n 6 6 Draw “the river” Divide both sides by 6 2.5 = n Simplify Check your answer 15 = 6(2.5) 3) Solve -3v = -129 1. 2. 3. 4. v = -126 v = -43 v = 43 v = 126 Answer Now x 12 4) Solve 4 You don’t like fractions? Let’s get rid of them! “Clear the fraction” by multiplying both sides of the equation by the denominator. 1. 2. 3. 4. x 4) Solve 12 4 Draw “the river” x Clear the fraction – 4 · 12 · 4 multiply both sides by 4 4 Simplify Check your answer x = -48 48 12 4 1. 2. 2x 5) Solve = 18 3 2x 3· = 18 · 3 Draw “the river” 3 Clear the fraction – 3. 4. 5. 6. multiply both sides by 3 Simplify Divide both sides by 2 Simplify Check your answer 2x = 54 2 2 x = 27 2(27) 18 3 6) Which step clears the fraction in 3b 12 5 1. 2. 3. 4. Multiply by 3 Multiply by 5 Multiply by -12 Multiply by -5 Answer Now 7) Solve 1. 2. 3. 4. b = -56 b = -14 b = 14 b = 56 Answer Now 4b 8 7