1. Lesson 10.4 Objective: To solve equations with variables on both sides of the equal sign Some equations have variables on both sides of the equal sign. To solve such equation, You may collect the variable terms on one side of the equal sign. Example : 12 + 4x = 10xSubtract 4x from both sides. – 4x – 4x 12 = 6xDivide both sides by 6. 6 6 2 = x Solution Check: 12 + 4(2) = 10(2) 20 = 20

2. Example: 50 + 9x = 4xSubtract 9x from both sides. – 9x – 9x 50 = – 5x Divide both sides by – 5. – 5 – 5 – 10 = x Solution Check: 50 + 9(-10) = 4(-10) 50 + (-90) = -40 – 40 = – 40

3. Example: Distribute the 5x – 10 = 3 + 2x Subtract 2x from both sides. – 2x 3x – 10 = 3 Add 10 to both sides +10 +10 3x = 13 Divide both sides by 3 3 3 x =or

4. Write an equation to find the value of x so that each pair of polygons have the same perimeter. then find each perimeter. 3x 7 x + 6 7 Pentagon = Rectangle 3x+3x+ 3x+ 3x+ 3x = 7 + x + 6 + x + 6 + 7 15x = 2x + 26 - 2x -2x 13x = 26 X = 2 Perimeter 15(2) =2(2) + 26 30 = 30

5. Verbal Models/Problem Solving Example: Hank’s video store charges $8.00 to rent a video game for five days and does not charge an annual membership fee. Bunker’s video only charges $3.00 for a five day rental but has a $50.00 membership fee per year. Find the number of rentals that would cost the same from each store. Hanks Fee Number Rented = Bunkers Fee Number Rented + Membership Fee 8 x = 3 x + 50 Subtract 3x from both sides 5x = 50 Divide both sides by 5 X = 10 If you rent 10 games per year, the cost would be the same.