++

= (2x'+3y+ (5x'+3x)- (8y'-3x'+2x+3y)

=2x'+3y+5x'+3x-8y'+3x'-2x-3y

= 2x'+5x'+3x'-8y'+3y-3y+3x-2x

= 10x'-8y'+x

++=10x'-8y'+x

Let's x' is the x to the power 2 and

y' is the y to the power 2.