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3x+2+4x+6x= 32+2+42+62=6+2+8+12=28
6x-2y+5x+4y=62-2*(-2)+52+4(-2)=12+4+10-8=18
6x-8-2x-3-4x+2+y=60-8-20-3-40+2+\frac{1}{2}=0-8-0-3-0+2+\frac{1}{2}=-8$\frac{1}{2}$
3k-2m+9k-m-4k-m-m=31-21+91-1-4*1-1-1=3-2+9-1-4-1-1=3
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a)
-5+t-6-7t+8t+2+2t= -5-3,2-6-7*(-3,2)+8*(-3,2)+2+2*(-3,2)=-5-3,2-6+22,4-25,6+2-6,4=
-46,2 +24,4= -21,8
b)-7x+6y+3x-2y+x-3y= -7*(\frac{-2}{3} + 6*\frac{4}{7} + 3*\frac{-2}{3} - 2*\frac{4}{7} - \frac{-2}{3} - 3*\frac{4}{7}=
\frac{14}{3} + \frac{24}{7} - 2- \frac{8}{7} - \frac{2}{3} - \frac{12}{7}=
\frac{98}{21} + \frac{72}{21} - 2 - \frac{24}{21} - \frac{14}{21} - \frac{36}{21}=
\frac{170}{21} - 2- \frac{74}{21}=
-2 - \frac{96}{21}= -2 - 4$\frac{12}{21}= -6\frac{12}{21}= -6\frac{4}{7}$