Download presentation
Presentation is loading. Please wait.
Published byNelson Woolery Modified over 9 years ago
1
EXAMPLE 2 Look for a pattern Paramotoring A paramotor is a parachute propelled by a fan-like motor. The table shows the height h of a paramotorist t minutes after beginning a descent. Find the height of the paramotorist after 7 minutes.
2
EXAMPLE 2 Look for a pattern SOLUTION The height decreases by 250 feet per minute. You can use this pattern to write a verbal model for the height. An equation for the height is h = 2000 – 250t.
3
EXAMPLE 2 Look for a pattern So, the height after 7 minutes is h = 2000 – 250(7) = 250 feet. ANSWER
4
EXAMPLE 3 Draw a diagram Banners You are hanging four championship banners on a wall in your school’s gym. The banners are 8 feet wide. The wall is 62 feet long. There should be an equal amount of space between the ends of the wall and the banners, and between each pair of banners. How far apart should the banners be placed? SOLUTION Begin by drawing and labeling a diagram, as shown below.
5
EXAMPLE 3 Draw a diagram From the diagram, you can write and solve an equation to find x. x + 8 + x + 8 + x + 8 + x + 8 + x = 62 5x + 32 = 62 Subtract 32 from each side. 5x5x = 30 x=6 Divide each side by 5. Combine like terms. Write equation. The banners should be placed 6 feet apart. ANSWER
6
EXAMPLE 4 Standardized Test Practice SOLUTION STEP 1 Write a verbal model. Then write an equation. An equation for the situation is 460 = 30g + 25(16 – g).
7
EXAMPLE 4 Standardized Test Practice Solve for g to find the number of gallons used on the highway. STEP 2 460 = 30g + 25(16 – g) 460 = 30g + 400 – 25g 460 = 5g + 400 60 = 5g 12 = g Write equation. Distributive property Combine like terms. Subtract 400 from each side. Divide each side by 5. The car used 12 gallons on the highway. ANSWER The correct answer is B. CHECK: 30 12 + 25(16 – 12) = 360 + 100= 460
8
GUIDED PRACTICE for Examples 2, 3 and 4 SOLUTION 2. PARAMOTORING: The table shows the height h of a paramotorist after t minutes. Find the height of the paramotorist after 8 minutes. The height decreases by 210 feet per minute. –210 24002190198017701560
9
GUIDED PRACTICE for Examples 2, 3 and 4 An equation for the height is h = 2400 – 210t. h = 2400 – 210t So, the height after 8 minutes is h = 2400 – 210(8) = 720 feet. ANSWER You can use this pattern to write a verbal model for the height.
10
GUIDED PRACTICE for Examples 2, 3 and 4 3. SOLUTION WHAT IF? In Example 3, how would your answer change if there were only three championship banners? Begin by drawing and labeling a diagram, as shown below. From the diagram, you can write and solve an equation to find x.
11
GUIDED PRACTICE for Examples 2, 3 and 4 x + 8 + x + 8 + x + 8 + x = 62 4x + 24 = 62 Subtract 24 from each side. 4x4x = 38 x=9.5 Divide each side by 4. Combine like terms. Write equation. The space between the banner and walls and between each pair of banners would increase to 9.5 feet. ANSWER
12
GUIDED PRACTICE for Examples 2, 3 and 4 SOLUTION 4. FUEL EFFICIENCY A truck used 28 gallons of gasoline and traveled a total distance of 428 miles. The truck’s fuel efficiency is 16 miles per gallon on the highway and 12 miles per gallon in the city. How many gallons of gasoline were used in the city? STEP 1 Write a verbal model. Then write an equation. 428 16 g 12(28 – g) =+
13
GUIDED PRACTICE for Examples 2, 3 and 4 Solve for g to find the number of gallons used on the highway. STEP 2 428 = 16(28 – g) + 12g 428 = 448 – 16g + 12g 428 = 448 – 4g – 20 = – 4g 5 = g Write equation. Distributive property Combine like terms. Divide each side by 4. The car used 5 gallons on the highway. CHECK: 16(28 – 5) + 12 5 = 368 + 60 = 428 An equation for the situation is 428 = 16(28 – g) + 12g. Subtract 428 from each side.
Similar presentations
© 2024 SlidePlayer.com. Inc.
All rights reserved.