1 / 19

2.4 Solve Multi-Step Equations

2.4 Solve Multi-Step Equations. You will solve multi-step equations. How do you solve multi-step equations?. 30. 5 x. =. 5. 5. EXAMPLE 1. Solve an equation by combining like terms. Solve 8 x – 3 x – 10 = 20. 8 x – 3 x – 10 = 20. Write original equation. 5 x – 10 = 20.

emilie
Download Presentation

2.4 Solve Multi-Step Equations

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. 2.4 Solve Multi-Step Equations • You will solve multi-step equations. • How do you solve multi-step equations?

  2. 30 5x = 5 5 EXAMPLE 1 Solve an equation by combining like terms Solve 8x – 3x – 10 = 20. 8x – 3x – 10 = 20 Write original equation. 5x – 10 = 20 Combine like terms. 5x – 10 + 10= 20 + 10 Add 10 to each side. 5x = 30 Simplify. Divide each side by 5. x = 6 Simplify.

  3. SOLUTION When solving an equation, you may feel comfortable doing some steps mentally. Method 2 shows a solution where some steps are done mentally. EXAMPLE 2 Solve an equation using the distributive property Solve 7x +2(x + 6) = 39.

  4. METHOD2 Do Some Steps Mentally = 9x 27 9 9 EXAMPLE 2 METHOD1 Show All Steps 7x + 2(x + 6) = 39 7x + 2(x + 6) = 39 7x + 2x + 12 = 39 7x + 2x + 12 = 39 9x + 12 = 39 9x + 12 = 39 9x + 12 – 12= 39 – 12 9x = 27 9x = 27 x = 3 x =3

  5. SOLUTION ANSWER In Step 2, the distributive property is used to simplify the left side of the equation. Because –4(x– 3) = –4x + 12, Step 2 should be 5x – 4x + 12 = 17. The correct answer is D. A B C D EXAMPLE 3 Standardized Test Practice

  6. 1. 9d – 2d + 4 = 32 ANSWER 4 for Examples 1, 2, and 3 GUIDED PRACTICE Solve the equation. Check your solution.

  7. 2. 2w + 3(w + 4) = 27 ANSWER 3 EXAMPLE 2 for Examples 1, 2, and 3 GUIDED PRACTICE Solve the equation. Check your solution.

  8. 6x – 2(x – 5) = 46 3. ANSWER 9 EXAMPLE 2 for Examples 1, 2, and 3 GUIDED PRACTICE Solve the equation. Check your solution.

  9. 3 Solve . (3x + 5) = –24 2 (3x + 5) = –24 2 (3x + 5) = (–24) Multiply each side by , the reciprocal of. 3 3 2 3 2 3 2 2 3 3 2 EXAMPLE 4 Multiply by a reciprocal to solve an equation Write original equation. 3x + 5 = –16 Simplify. 3x = –21 Subtract 5 from each side. x = –7 Divide each side by 3.

  10. 4. (z – 6) = 12 ANSWER 22 3 4 EXAMPLE 4 for Example 4 Multiply by a reciprocal to solve an equation GUIDED PRACTICE Solve the equation. Check your solution.

  11. 5. (3r + 4) = 10 ANSWER 7 2 5 EXAMPLE 4 for Example 4 Multiply by a reciprocal to solve an equation GUIDED PRACTICE Solve the equation. Check your solution.

  12. 6. – (4a – 1) = 28 ANSWER –8.5 4 5 EXAMPLE 4 for Example 4 Multiply by a reciprocal to solve an equation GUIDED PRACTICE Solve the equation. Check your solution.

  13. SUMMER CAMP You are planning a scavenger hunt for 21 campers. You plan to have 5 teams. One camper from each team will be the recorder and the rest will be searchers. How many searchers will each team have? EXAMPLE 5 Write and solve an equation

  14. SOLUTION Let sbe the number of searchers on a team. Then 1 + s is the total number of campers on each team. EXAMPLE 5 Write and solve an equation

  15. ANSWER Because 4 searchers per team would require a total of 5(1 + 4) = 25 campers, 4 teams will have 3 searchers and 1 team will have 4 searchers. EXAMPLE 5 Write and solve an equation Write equation. 21 =5(1 + s) Distributive property 21 = 5 + 5s Subtract 5 from each side. 16 =5s 3.2 = s Divide each side by 5.

  16. 7. WHAT IF? In Example 5, suppose you decide to use only 4 teams. How many searchers should there be on each team? ANSWER There will be 5 searchers on one team and 4 searchers on the other teams. EXAMPLE 5 for Example 5 Write and solve an equation GUIDED PRACTICE

  17. ANSWER 2 ANSWER 11 ANSWER –4 Daily Homework Quiz Solve the equation. 1.8g–2+g=16 2.3b+2(b–4)=47 3. –6 + 4(2c+ 1) = –34

  18. 4.(x – 6) = 12 Joe drove 405 miles in 7 hours. He drove at a rate of 55 miles per hour during the first part of the trip and 60 miles per hour during the second part. How many hours did he drive at a rate of 55 miles per hour? 5. 2 3 ANSWER 3 h ANSWER 24 Daily Homework Quiz

  19. You will solve multi-step equations. • How do you solve multi-step equations? • To solve multi-step equations, first simplify one or both sides and then use inverse operations. • If a fraction is being multiplied by a quantity, use reciprocals to simplify instead of the distributive property. To solve a multi-step equation, first simplify and combine like terms. After simplifying, use inverse operations to isolate the variable.

More Related