Slope Word Problems

1. Slope Word Problems

2. Lesson Objective: 4.01a Students will know how to solve word problems using slope Slope Word Problems

3. In 2005, Joe planted a tree that was 3 feet tall. In 2010, the tree was 13 feet tall. Assuming the growth of the tree is linear, what was the rate of growth of the tree? Slope Word Problems

4. In 2005, Joe planted a tree that was 3 feet tall. In 2010, the tree was 13 feet tall. Assuming the growth of the tree is linear, what was the rate of growth of the tree? What does “rate of growth” mean? Slope! Slope Word Problems

5. Remember the slope equation: In order to find the slope we need two points Slope Word Problems y2 – y1 m = x2 – x1

6. In 2005, Joe planted a tree that was 3 feet tall. In 2010, the tree was 13 feet tall. Assuming the growth of the tree is linear, what was the rate of growth of the tree? Remember, x is always years, so replace x2 with the second year and x1 with the first Slope Word Problems y2 – y1 m = x2 – x1 2010 – 2005

7. In 2005, Joe planted a tree that was 3 feet tall. In 2010, the tree was 13 feet tall. Assuming the growth of the tree is linear, what was the rate of growth of the tree? Replace y2 with the height from the second year and y1 with the first Slope Word Problems y2 – y1 13 – 3 m = 2010 – 2005

8. Simplify the top Simplify the bottom Simplify the fraction to get m. Keep it as a fraction if it can’t be simplified Slope Word Problems 10 13 – 3 m = 2 2010 – 2005 5

9. In 2005, Joe planted a tree that was 3 feet tall. In 2010, the tree was 13 feet tall. Assuming the growth of the tree is linear, what was the rate of growth of the tree? The slope is 2, so the tree grows 2 feet per year Slope Word Problems m = 2

10. In 1995 a public library had 16,000 books on its shelves. In 1999 the library had 19,000 books. Assuming a linear increase, how many books were added to the library each year? Slope Word Problems

11. In 1995 a public library had 16,000 books on its shelves. In 1999 the library had 19,000 books. Assuming a linear increase, how many books were added to the library each year? We’re looking for how many for each year, usually the word “each” means slope. Slope Word Problems

12. In 1995 a public library had 16,000 books on its shelves. In 1999 the library had 19,000 books. Assuming a linear increase, how many books were added to the library each year? Years are always x so replace the x’s with the years Replace the y’s with the number of books for each year Slope Word Problems (1995, 16000), (1999, 19000) (1995, y1), (1999, y2) (x1, y1), (x2, y2)

13. Replace y2 with 19000 and y1 with 16000 Replace x2with 1999 and x1with 1995 Simplify the top and the bottom Reduce the fraction Slope Word Problems (1995, 16000), (1999, 19000) y2 – y1 19000 – 16000 3000 m = 750 x2– x1 1999 – 1995 4

14. In 1995 a public library had 16,000 books on its shelves. In 1999 the library had 19,000 books. Assuming a linear increase, how many books were added to the library each year? m = 750, therefore the library adds 750 books each year Slope Word Problems m = 750

15. Monica feeds her dog the same amount of dog food each day from a very large bag. ON the 3rd day, she has 44 cups left in the bag, and on the 11th day she has 28 cups left. How many cups of food does she feed her dog a day? Slope Word Problems

16. Wendy bought a car for $25,000 and its value depreciated linearly. After 3 years the value was $21,250. What was the amount of yearly depreciation? Slope Word Problems

17. Jamal’s parents give him $20 to spend at camp. Jamal spends the same amount of money on snacks each day. After 4 days he has $12 left. How much money is he spending each day? Slope Word Problems