1 / 9

EXAMPLE 4

. . . . 7. 7. 7. 7. x – 4 = ±. x = 4 ±. ANSWER. The solutions are 4 + 6.65 and 4 – 1.35. EXAMPLE 4. Solve a quadratic equation. Solve 6( x – 4) 2 = 42 . Round the solutions to the nearest hundredth. 6( x – 4) 2 = 42. Write original equation. ( x – 4) 2 = 7.

aheard
Download Presentation

EXAMPLE 4

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.    7 7 7 7 x – 4 = ± x= 4 ± ANSWER The solutions are 4 + 6.65 and 4 –1.35. EXAMPLE 4 Solve a quadratic equation Solve 6(x – 4)2 = 42. Round the solutions to the nearest hundredth. 6(x – 4)2 = 42 Write original equation. (x – 4)2 = 7 Divide each side by 6. Take square roots of each side. Add 4 to each side.

  2. EXAMPLE 4 Solve a quadratic equation CHECK To check the solutions, first write the equation so that 0 is on one side as follows: 6(x – 4)2 – 42 = 0. Then graph the related function y = 6(x – 4)2 – 42. The x-intercepts appear to be about 6.6 and about 1.3. So, each solution checks.

  3. EXAMPLE 5 Solve a multi-step problem SPORTS EVENT During an ice hockey game, a remote-controlled blimp flies above the crowd and drops a numbered table-tennis ball. The number on the ball corresponds to a prize. Use the information in the diagram to find the amount of time that the ball is in the air.

  4. EXAMPLE 5 Solve a multi-step problem SOLUTION STEP1 Use the vertical motion model to write an equation for the height h(in feet) of the ball as a function of timet(in seconds).

  5. EXAMPLE 5 Solve a multi-step problem h =–16t2+ vt + s Vertical motion model h =–16t2+ 0t + 45 Substitute for vand s. STEP2 Find the amount of time the ball isinthe air by substituting17forhand solving fort.

  6. 28 = t2 16 1.32 t EXAMPLE 5 Solve a multi-step problem h = – 16t2 + 45 Write model. 17 = – 16t2 + 45 Substitute 17 for h. Subtract45from each side. –28 = – 16t2 Divide each side by16.  28 = t Take positive square root. 16 Use a calculator.

  7. ANSWER The ball is in the air for about 1.32 seconds EXAMPLE 5 Solve a multi-step problem

  8. ANSWER ANSWER –1, 5 0.35, 5.65 ANSWER –7.83, –2.17 EXAMPLE 1 for Examples 4 and 5 Solve quadratic equations GUIDED PRACTICE Solve the equation. Round the solution to the nearest hundredth if necessary. 10. 2(x – 2)2 = 18 11. 4(q – 3)2 = 28 12. 3(t + 5)2 = 24

  9. 13. WHAT IF? In Example 5, suppose the table-tennis ball is released 58 feet above the ground and is caught 12 feet above the ground. Find the amount of time that the ball is in the air. Round your answer to the nearest hundredth of a second. ANSWER The ball is in the are for about 1.70 second. EXAMPLE 1 for Examples 4 and 5 Solve quadratic equations GUIDED PRACTICE

More Related