1. 5a + 4b + 3c + 2d = 16

1. 10a + 8b + 6c + 4d = 32

eliminasi (1) dan (4)

10a + 8b + 6c + 4d = 32

10a + 7b + 6c + 4d = 30

___________________-

b = 2

eliminasi (1) dan (2)

5a + 4b + 3c + 2d = 16

2a + 3b + 5c + 2d = 9

__________________-

3a + b -2c = 7

3a + 2 -2c = 7

3a -2c = 5 ..... (4)

2. 2a + 3b + 5c + 2d = 9

2. 4a + 6b + 10c + 4d = 18

eliminasi (2) dan (3)

4a + 6b + 10c + 4d = 18

4a + 5b + 2c + 3d = 21

___________________-

b + 8c + d = -3

8c + d = -5 ..... (5)

3. 4a + 5b + 2c + 3d = 21

3. 12a + 15b + 6c + 9d = 63

eliminasi (3) dan (4)

12a + 15b + 6c + 9d = 63

10a + 7b + 6c + 4d = 30

____________________-

2a + 8b + 5d = 33

2a + 5d = 33 -16

2a + 5d = 17 ..... (6)

3a -2c = 5 ..... (4)

12a -8c = 20 ..... (4)

8c = 12a -20 ..... (4)

8c + d = -5 ..... (5)

8c = -5 -d ..... (5)

substitusi 8c dari (4) ke (5)

12a -20 = -5 -d

12a + d = 15 ..... (7)

60a + 5d = 75 ..... (7)

eliminasi (6) dan (7)

60a + 5d = 75

2a + 5d = 17

____________-

58a = 58

a = 1

substitusi a ke (6)

2a + 5d = 17

2 + 5d = 17

5d = 15

d = 3

substitusi d ke (5)

8c + d = -5

8c + 3 = -5

8c = -8

c = -1

maka :

a = 1

b = 2

c = -1

d = 3