Word Problems
Solve by Graphing
Solve by Substitution
Solve by Elimination
Is the Solution Correct?
100

There are 13 animals in the barn. Some are chickens and some are pigs. There are 40 legs in all. How many of each animal are there?

 6 chickens and 7 pigs

100

By graphing, the solution to the system

y = x

y = -x

(0,0) 

100

The solution to the system

x + y = 2

y = 3

(-1,3) 

100

The solution to the system 

x + 5y = 12 

-x +y = 0

 (2,2) 

100

(4,5) is the solution to the following system?

 4x - y = 12 

x + 6y = 13

 NO !

200

Find the value of two numbers if their sum is 12 and their difference is 4.

(8,4) 

200

By graphing, the solution to the system

y = 3x - 4

y = -3x + 2

(1,-1)

200

2y - x = 4

10y - x = 20

 (4,2) 

200

The solution to the system

-4x - 2y = -12

4x + 8y = -24

 (6,-6)

200

(0,-4) the solution to the system 

y = -20x + 1 

20x + y = 6

 No

300

John went to Yellow Stone National Park one day this summer. All of the people at the park were either hiking or bike riding. There were 178 more hikers than bike riders. If there were a total of 676 people at the park, how many were hiking and how many were riding their bikes?

 427 hikers and 249 bikers 

300

By graphing, the solution to the system

y = (1/3)x + 2

y = -x - 2

 (-3,1) 

300

The solution to the system

y = 6x - 11

-2x - 3y = -7

(2,1) 

300

The solution to the system

5x + y = 9

10x - 7y = -18

 (1,4)

300

(-2,1) is a solution to the system 

6x - 3y = -15 

2x + y = -3

 Yes

400

Harold had a summer lemonade stand where he sold small cups of lemonade for $1.25 and large cups for $2.50. If Harold sold a total of 155 cups of lemonade and collected a total of $265, how many cups of each type did he sell?

 98 small cups and 57 large cups of lemonade

400

By graphing, the solution to the system

y = -(3/2)x - 4

y = (1/2)x + 4

 (-4,2) 

400

The solution to the system

-3x + 3y = 4

-x + y = 3

no solution

400

The solution to the system

-4x + 9y = 9

x = 3y - 6

(9,5)

400

No solution describes the solution to the following system 

y = 3x + 4 

y = -x - 4

 No

500

Phil bought 6 new compact disks and 2 used compact disks for $127.92. At the same prices, Mackenzie bought 3 new compact disks and 8 used compact disks for $133.89. Find the cost of buying a single used compact disk.

9.99 

500

By graphing, the solution to the system

y = (5/4)x - 2

y = (5/4)x -1

 no solution

500

The solution to the system

-5x - 8y = 17

2x - 7y = -17

 (-5,1) 

500

The solution to the system

2x + 8y = 6

-5x - 20y = -15

infinite number of solutions

500

(-3,-1) is the solution to 

y=(4/3)x + 3

 (2/3)x + y = -3

 (-3,-1)