1 / 19

Algebra 1

Algebra 1. Section 2.5. Solving Two-Step Equations. The operations done to a variable must be undone using inverse operations in reverse order. Example 1. Solve 2 x + 6 = 21. 2 x + 6 = 21. 2 x + 6 – 6 = 21 – 6 . 2 x = 15. Example 1. 2 x = 15. 2 x. 15. = . 2. 2. 15.

cosmo
Télécharger la présentation

Algebra 1

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Algebra 1 Section 2.5

  2. Solving Two-Step Equations The operations done to a variable must be undone using inverse operations in reverse order.

  3. Example 1 Solve 2x + 6 = 21. 2x + 6 = 21 2x + 6 – 6 = 21 – 6 2x= 15

  4. Example 1 2x = 15 2x 15 = 2 2 15 x = 2 Did you check your answer?

  5. Example 2 a Solve – 3.6 = -4.4. 1.5 a – 3.6 + 3.6 = -4.4 + 3.6 1.5 a = -0.8 1.5

  6. Example 2 a ( ) 1.5 = 1.5(-0.8) 1.5 -1.2 – 3.6 = -0.8 – 3.6 = -4.4 1.5 a a = -1.2 = -0.8 1.5

  7. Solving Equations of the Form ax + b = c Undo the addition or subtraction of the constant term. Undo the multiplication or division done to the variable.

  8. Example 3 x Solve – 7 = 2. 3 x x – 7 + 7 = 2 + 7 = 9 3 3

  9. Example 3 x ( ) x 3 = 3(9) = 9 3 3 x = 27

  10. Solving Word Problems Step 1: Read the Problem Draw a picture, if possible Assign a variable to the main unknown

  11. Solving Word Problems Step 2: Plan a Method of Attack Make a table, if possible Translate word phrases into expressions using the variable

  12. Solving Word Problems Step 3: Solve an Equation Write an equation Solve the equation

  13. Solving Word Problems Step 4: Check your Solution Have I answered all of the questions in the problem? What do the numbers represent? Are the answers reasonable?

  14. Example 4 Ninety-seven is twenty-four less than four times a number. 97 = 4x – 24

  15. Example 5 How many quarters must be removed from $2.64 to leave a total of $1.89? q = number of quarters 0.25q = value of the quarters 2.64 – 0.25q = 1.89

  16. Example 6 The grain elevator weighed Mr. Young’s truck at 17,760 lb before he dumped his wheat. The weight of the empty truck is 6180 lb. If the wheat weighed 60 lb/bu, how many bushels of wheat did he deliver to the elevator?

  17. Example 6 The grain elevator weighed Mr. Young’s truck at 17,760 lb before he dumped his wheat. The weight of the empty truck is 6180 lb. If the wheat weighed 60 lb/bu, how many bushels of wheat did he deliver to the elevator? b = bushels of wheat 60b = the weight of the wheat

  18. Example 6 The grain elevator weighed Mr. Young’s truck at 17,760 lb before he dumped his wheat. The weight of the empty truck is 6180 lb. If the wheat weighed 60 lb/bu, how many bushels of wheat did he deliver to the elevator? 60b + 6180 = 17,760

  19. Homework: pp. 72-74

More Related