`M(x)=A(x)-B(x)`
`M(x)=(2xy+6x-7y)-(3y+6xy-8x)`
`M(x)=2xy+6x-6y-3y-6xy+8x`
`M(x)=(2xy-6xy)+(6x+8x)-(6y+3y)`
`M(x)=-4xy+14x-9y`
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`N(x)=B(x)+A(x)`
`N(x)=(3y+6xy-8x)+(2xy+6x-7y)`
`N(x)=3y+6xy-8x+2xy+6x-7y`
`N(x)=(6xy+2xy)+(3y-7y)-(8x-6x)`
`N(x)=8xy-4y-2x`
\(M\left(x\right)=A\left(x\right)-B\left(x\right)\)
\(M\left(x\right)=2xy+6x-7y-3y-6xy+8x\)
\(M\left(x\right)=-4xy+14x-10y\)
\(N\left(x\right)=B\left(x\right)+A\left(x\right)\)
\(N\left(x\right)=3y+6xy-8x+2xy+6x-7y\)
\(N\left(x\right)=-4y+8xy-2x\)
A(x)-B(x) = ( 2xy+6x-7y ) - (3y+6xy-8x)
A(x)-B(x) = −4xy+14x−10y
B(x)+A(x) = (3y+6xy-8x) + ( 2xy+6x-7y )
B(x)+A(x) = 8xy−2x−4y
M(x)=A(x)-B(x) = 2xy+6x-7y - ( 3y+6xy-8x)
= 2xy + 6x-7y - 3y - 6xy + 8x
= ( 2xy - 6xy ) + ( 6x + 8x ) + ( -7y - 3y )
= -4xy + 14x - 10y
N(x)=B(x)+A(x) = 2xy+6x-7y + 3y+6xy-8x
= (2xy + 6xy) + ( 6x - 8x) + ( -7y + 3y)
= 8xy - 2x - 4y