Jawabanmu

2014-08-24T20:35:53+07:00
Jika A=x+2y-4
B=3x+4y+6
C=5x+6y+17 hitunglah
A. A+2b+3c
= x+2y-4+2(3x+4y+16)+3(5x+6y+17)
= x+2y-4+6x+8y+12+15x+18y+17
= x+6x+15x+2y+8y+18y-4+12+17
= 22x+28y+25
2014-08-24T20:47:02+07:00
A. a+2b+3c = (x+2y-4)+(6x+8y+12)+(15x+18y+51 )
                  = x+6x+15x+2y+8y+18y-4+12+51 = 22x+28y+59
B. 4a+b-c =( 4x+8y-16)+(3x+4y+6)-(5x+6y+17)
                =4x+3x-5x+8y+4y+6y-16+6+17 = 2x+18y+7
C. 2a+2b+c= (2x+4y+8)+(6x+4y+12)+(5x+6y+17)
                 = 2x+6x+5x+4y+4y+6y+8+12+17 = 13x+14y+37