no 5 dan 6 pakai cara ya :))

5. 48x + 48y = 2.304
    72x + 24y = 1.728

eliminasi
 
48x + 48y = 2.304
144x + 48y = 3.456

96x = 1152
x = 1152/96
x = 12

48x + 48y = 2.304
48(12) + 48y = 2.304
576 + 48y = 2.304
48y = 2.304 - 576
y = 1728/48
y = 36

2x + y
2(12) + 36
24 + 36
60 (a)

6. 4x + y = 4
    2x + 3y = 6

elimiasi

4x + y = 4
4x + 6y = 12

-5y = -8
y = 8/5

2x + 3y = 6
2x +3(8/5) = 6
2x = 6 - 24/5
x = (6/5)(1/2)
x= 6/30

x + y
6/30 + 8/5
6/30 + 48/30
 54/30
9/5 (a)