1. 1-26-11  Bellwork #42  HW, red pen, book on desk.

2. Solving Equations with Variables on Both Sides Lesson 7-5 p.355

3. Variables on Both Sides of the Equations  Consider an equation like this:  5x – 8 = 3x  What looks different about this equation?

4. Variables on Both Sides of the Equations  Consider an equation like this:  5x – 8 = 3x  What looks different about this equation?  Yes, there are x’s on both sides of the =

5. Variables on both sides  To solve this type of equation we need to get all the x’s on one side of the equation and all the numbers on the other side.  So,  5x – 8 = 3x  -5x -5xSubtract 5x from both sides  -8 = -2x  -2 -2Divide both sides by -2   4 = xSolve

6. Another example  Let’s try this one:  9a + 2 = 4a – 18  -4a -4aSubtract 4a from both sides  5a + 2 = -18(look familiar?)  -2 -2Subtract 2 from both sides  5a = -20  5 5Divide both sides by 5  a = -4Solve

7. Try This  4x + 4 = 2x + 36  -15 + 6b = -8b + 13

8. Try This  4x + 4 = 2x + 36x = 16  -15 + 6b = -8b + 13

9. Try This  4x + 4 = 2x + 36x = 16  -15 + 6b = -8b + 13b = 2

10. Try This Too Remember to distribute first: 2(x-4) = 3x 8r + 2 = 3(r – 1)

11. Try This Too Remember to distribute first: 2(x-4) = 3xx = -8 8r + 2 = 3(r – 1)

12. Try This Too Remember to distribute first: 2(x-4) = 3xx = -8 8r + 2 = 3(r – 1)r = -1

13. Agenda 1-26-11  PA #7  Pp.357 #10-18 all