Jawabanmu

2014-08-08T14:27:31+07:00
*bilangan pecahan di kali masuk dengan persamaan didalam kurung

1. 2/5 ( 15a - 20b ) - 1/2 ( 4a - 2b )
= [2/5(15a-20b)] -[1/2(4a-2b)]
=(6a-8b) - (2a-b)
=6a-2a-8b+b
=4a-7b

2. -1/3 ( 12x - 6y ) - ( x - 4y )
= [-1/3(12x-6y)]- (x-4y)
= (-4x+2y) -(x-4y)
= -4x-x +2y+4y
= -5x +6y

3. 2/7 ( 14p - 7q ) - 1/5 ( 10q - 5p )
=[2/7(14p-7q) - 1/5(10q-5p)]
=(4p-2q) -(2q-p)
=4p+p -2q-2q
=5p-4q

semoga membantu :-)
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