Solve Equations With Variables on Both Sides

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Solve Equations With Variables on Both Sides
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Test Results

• Second Period 79.31
• Fourth Period 76.46
• Sixth Period 77.84
• Seventh Period 80.90
• Eighth Period 73.39

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Test Answers

• 1. 12
• 2. D
• 3. C
• 4. D
• 5. 110F
• 6. -23
• 7. A
• 8. 2430
• 9. D
• 10. 16 years

• 11. x 15
• 12. 4
• 13. D
• 14. x 7
• 15. 5 birdhouses
• 16. 1.90
• 17. 13 5/9
• 18. x 40
• 19. x ¾
• 20. x -6

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Example 1

• 3x 4 5x 8
• Since the xs are on opposite sides of the equal
  sign, you must get rid of one of them by using
  inverse operations.
• I like to get rid of the one on the right side
  so that the x ends up on the left side.
• So, I will subtract 5x from both sides.

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Example 1

• 3x 4 5x 8
• 3x 5x 4 5x 5x 8 Simplify
• -2x 4 -8 Now you can solve this equation!
• Subtract 4 from both sides.
• -2x 4 4 -8 4
• -2x -12 Divide both sides by 2
• x 6

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Example 2

• 4(1 2x) 4 6x
• 4 8x 4 6x
• 4 8x 6x 4 6x 6x
• -2x 4 4
• -2x 4 4 4 4
• -2x 0
• x 0

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Example 3

• 9 5x 5x 9
• 9 5x 5x 5x 9 5x
• 9 9
• Since all of the variables are gone, this is
  different.
• Does 9 9?
• Yes, so it is what we call an Identity (that
  means there are infinitely many answers).
• So, the answer is all real numbers (R).

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Example 4

• 6x 1 6x 8
• Subtract 6x from both sides.
• 6x 6x 1 6x 6x 8
• -1 -8
• Again, both variables are gone. Is 1 -8 true?
• No, so it is no solution (There arent any
  numbers that will work.)
• The answer is no solution or

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From tonights work

• 33 Justin and Tyson are beginning an exercise
  program to train for football season. Justin
  weighs 150 lb and hopes to gain 2 lb per week.
  Tyson weighs 195 lb and hopes to lose 1 lb per
  week.
• If the plan works, in how many weeks will the
  boys weigh the same?

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Another one

• Rapid Rental Car company charges a 40 rental
  fee, 15 for gas, and 0.25 per mile driven. For
  the same car, Capital Cars charges 45 for rental
  and gas and 0.35 per mile.
• A. Find the number of miles for which the
  companies charges will be the same.
• B. The Barre family estimates that they will
  drive about 95 miles during their vacation.
  Which company should they choose?
• C. If they extend their vacation and travel about
  120 miles. Should they rent from the same
  company?

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Try these

• 2x 16 x 25
• 14 (2x 5) -2x 9
• 0.7m 0.9m 2.4 0.2m
• x 1 4x 1
• 5(x7) 2(x - 20) x

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Try these-answers

• 2x 16 x 25 x -41
• 14 (2x 5) -2x 9 R
• 0.7m 0.9m 2.4 0.2m
• x 1 4x 1 x 0
• 5(x7) 2(x - 20) x x -37.5