MATH 27
SOLVING TWO EQUATIONS - TWO UNKNOWNS
BY SUBSTITUTION METHOD
PRACTICE
1. 3x + 2y = 11
y = x + 3
2. 3x - y = 2
y = 2x - 1
3. 3x - y = -5
y = x + 4
4. x = 2y - 3
2x - 3y = -5
5. x = 3y - 1
3x + 4y = 10
6. y = 2 - 3x
6x + 2y = 7
7. x = 2 - y
3x + 3y = 6
8. 3x + 5y = -6
x = 5y + 3
9. y = 2x + 3
4x - 3y = 1
10. 4x - 3y = -1
y = 2x - 3
11. 3x - 7y = 28
x = 3 - 4y
12. 7x + y = 14
2x - 5y = -33
13. 3x + y = 4
4x - 3y = 1
14. x - 4y = 9
2x - 3y = 11
15. 3x - y = 6
x + 3y = 2
16. 4x + 3y = 0
2x - y = 0
17. 5x + 2y = 0
x - 3y = 0
18. y = 2x - 7
y = 4x + 5
19. 3x - y = 11
2x + 5y = -4
20. x = 4y - 2
x = 6y + 8
Solutions:
|
1 |
(1, 4) |
11 |
(7, -1) |
|
2 |
(1, 1) |
12 |
(1, 7) |
|
3 |
(-1, 3) |
13 |
(1, 1) |
|
4 |
(-1, 1) |
14 |
(17/5, -7/5) |
|
5 |
(2, 1) |
15 |
(2, 0) |
|
6 |
No solution |
16 |
(0, 0) |
|
7 |
same solutions |
17 |
(0, 0) |
|
8 |
(-3/4, -3/4) |
18 |
(-6, -19) |
|
9 |
(-5, -7) |
19 |
(3, -2) |
|
10 |
(5, 7) |
20 |
(-22, -5) |