Ch. 6 Systems of Linear Equations

Substitution Method

100

y=x+5

3x+y=25

(5,10)

200

x=y-2

4x+y=2

(0,2)

300

3x+y=6

4x+2y=8

(2,0)

400

2x+3y=4

4x+6y=9

No Solution

500

x-y=1

3x=3y+3

infinitely many solutions

Elimination Method

100

5m-p=7

7m-p=11

(2,3)

200

7f+3g=-6

7f-2g=-31

(-3,5)

300

6a-3b=27

2a-3b=11

(4,-1)

400

6r-6t=6

3r-6t=15

(-3,-4)

500

11f+14g=13

11f+10g=25

(5,-3)

Elimination Method

100

8x+5y=38

-8x+2y=4

(1,6)

200

5m-2p=24

3m+2p=24

(6,3)

300

9x+6y=78

3x-6y=-30

(4,7)

400

-3x-8y=-24

3x-5y=4.5

(4,1.5)

500

3j+4k=23.5

8j-4k=4

(2.5,4)

Guess my numbers

100

I have two numbers in my head. When you added them up you get 46 and when you subtract them you get 16. What are my two numbers?

31 and 15

200

The sum of two numbers is 28 and their difference is 4. What are the numbers? 

16 and 12

300

Find the two numbers whose sum is 29 and whose difference is 15. What are the numbers?

22 and 7

400

The sum of two numbers is 70. One number is ten more than twice the other number. What are the numbers?

50 and 20

500

Two times a number added to another number is 25. Three times the first number minus the other number is 20. What are the numbers? 

9 and 7