Tolong bantu nomer 4-6

No 4)

Berarti :

1 + a = 3

a = 2

b+3+15a = 42

b+3+30 = 42

33+b = 42

b = 9

a – b = 2-9 = -7

No 5)

3+(-4) = 3n + 2 + 5

-1 = 3n + 7

3n = -8

n = -8/3

No 6)

Berarti :

2m = n

4n = 5+3m

4(2m) = 5+3m

8m = 5+3m

5m = 5

m = 1

2(1) = n

n = 2

m – n = 1-2 = -1