Download 8-6 Systems Word Problems - White Plains Public Schools

SWBAT: Solve system of linear equation word problems
Lesson 8-5
Do Now:
Solve the following system of equations using BOTH substitution AND elimination:
SUBSTITUTION
ELIMINATION
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SWBAT: Solve system of linear equation word problems
Lesson 8-5
Break Even/Same Cost
1) One cable company provider has a $60 setup fee and charges $80 per month, and another
cable provider has a $160 equipment fee and charges $70 per month.
a) Create two functions to model the cost of each service.
b) How many months will the costs be the same and what is the total fee?
2)
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SWBAT: Solve system of linear equation word problems
Lesson 8-5
Creating Linear Systems Models from Tables
3)
A small town in the mountain needs to buy road salt for the coming winter.
companies that use the following pricing table.
It has found two
a) Use the table for the same product from two different companies to create a linear system.
b) Then solve the system to determine when the cost of the product will be the same and
what the price will be.
Road Salt
(tons)
5
10
15
Company 1
Company 2
$1775
$3350
$4925
$2750
$4000
$5250
3
SWBAT: Solve system of linear equation word problems
Lesson 8-5
Money Problems
4)
5)
4
SWBAT: Solve system of linear equation word problems
Lesson 8-5
LESSON PRACTICE
5
SWBAT: Solve system of linear equation word problems
Lesson 8-5
LESSON PRACTICE ANSWERS
6
SWBAT: Solve system of linear equation word problems
Lesson 8-5
1) Use the table for the same product from two different companies to create a linear system.
Then solve the system to determine when the cost of the product will be the same and
what the price will be.
Two dry cleaning companies offer a home pick-up and delivery service. The monthly cost
depends on the number of garments laundered, and is shown in
the table.
Number of
Garments
5
10
15
Company 1
Company 2
$55.25
$75.50
$95.75
$31.35
$57.50
$83.75
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SWBAT: Solve system of linear equation word problems
Lesson 8-5
Use the table for the same product from two different companies to create a linear system.
Then solve the system to determine when the cost of the product will be the same and what
the price will be.
Two online retailers sell organic vanilla extract by the ounce using the following pricing chart.
Vanilla
Extract
(oz)
2
3
4
5
Chef Mate
Grocery
Gourmet
$12.50
$17.25
$22
$26.75
$17
$21
$25
$29
c) Use the table for the same product from two different companies to create a linear system.
Then solve the system to determine when the cost of the product will be the same and what
the price will be.
A restaurant needs to stock paper towels in its kitchen and bathrooms. It has found two
vendors using the following case price chart.
Paper Towels
(case)
5
10
15
Company 1
Company 2
$300.20
$480.15
$660.10
$220.20
$420.15
$620.10
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SWBAT: Solve system of linear equation word problems
Lesson 8-5
System of equations number problems.
Two numbers have a sum of 1,212 and a
difference of 518. What are the two
numbers?
2) The sum of two numbers is 361 and the
difference between the two numbers is 173.
What are the two numbers
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SWBAT: Solve system of linear equation word problems
Lesson 8-5
System of equations money problems
3) A friend bought 2 boxes of pencils and 8 notebooks for school and it cost him $11. He went
back to the store the same day to buy school supplies for his younger brother. He spent
$11.25 on 3 boxes of pencils and 5 notebooks. How much would 7 notebooks cost?
1) You want to burn 225 calories while exercising at the gym. The number of calories that
you burn per minute on different machines at the gym is shown below.
Suppose you have 40 minutes to exercise at the gym and you want to use the stair machine
and stationary bike.
How many minutes should you spend on each machine so that you burn 225 calories.
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SWBAT: Solve system of linear equation word problems
Lesson 8-5
System of equations geometry problems
1) The cost of 3 markers and 2 pencils is $1.80. The cost of 4 markers and 6 pencils is $2.90.
What is the cost of each item? Include appropriate units in your answer.
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