1. Lesson 6.4 Applications of Linear Systems

2. Example 1 The sum of two numbers is 20. The difference between three times the larger and twice the smaller is 40.Find the two numbers.

3. Example 2 The sum of two numbers is 30. The sum of twice the smaller and the larger is 36. Find the two numbers.

4. Example 3 Suppose a corvette club publishes a newsletter. Expenses are $.90 for printing and mailing each copy, plus $600 total for research and writing. The price of the newsletter is $1.50 per copy. How many copies of the newsletter must the club sell to break even?

5. Example 4 Suppose an antique car club publishes a newsletter. Expenses are $.35 for printing and mailing each copy, plus $770 total for research and writing. The price of the newsletter is $.55 per copy. How many copies of the newsletter must they sell to break even?

6. Example 5 The Zippy Coaster has 20 cars, some hold 3 people and some hold 4 people. There is room for 72 people altogether. How many 3 passenger cars are there? How many 4 passenger cars are there?

7. Example 6 At the student store, Tim bought for 4 pens and 5 pencils for $6.71. Tess bought 5 pens and 3 pencils for $7.12. Find the price of each pen and pencil.

8. Example 7 Tom’s age plus 3 times Jerry’s age is 45. Four times Tom’s age plus 9 times Jerry’s age is 153. How old are Tom and Jerry?