Jawabanmu

2014-07-17T17:34:13+07:00
1. 2(m-5) dari 3(7-n)
= 2m-10+21-3n
= 2m-3n+11
2. 5(x-2y+1) dari -4(y-3)
= 5x-10y+5+(-4y)+12
= 5x-10y+5-4y+12 
= 5x-10y-4y+5+12
=5x-14y+17
3. -m+6m-5 dari -4m+7n
=-4m+7n - (-m+6m-5)
= -4m+7n+m-6m+5
=-4m+m-6m+7n+5
=-9m+7n+5
4. 7(m-2n) dari 5(-m+3n)
= -5m+15n - (7m-14n)
=-5m+15n-7m+14n
=-5m-7m+15n+14n
=-12m+29n

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