ex1/ A= 4x-(6x-7)-7
= 4x-6x+7-7
= -2x
B= -(7x-8)+6x-3
= -7x+8+6x-3
= -7x+6x+8-3
= -x+5
C= -5x-(-x-3)-6
= -5x+x+3-6
= -4x-3
D=8+(10x+10)-3x
= 8+10x+10-3x
= 8+10+10x-3x
= 18+7x
E= -9+(2x-3)-2x
= -9+2x-3-2x
= -9-3+2x-2x
= -12
F = -5-(3x-9)-6x
= -5-3x+9-6x
= -5+9-3x-6x
= 4-9x
ex2/ A= 4x*8 = 32x
B = 6*9x = 54x
C = 4*(-4x-2)+7x
= -16x-8+7x
= -9x-8
D= 6x-1+(5x+10)*6
= 6x-1+6*(5x+10)
= 6x-1+30x+60
= 6x+30x-1+60
= 36x+59
E= 9+(-4x+10)*9
= 9+9*(-4x+10)
= 9-36x+90
=9+90-36x
= 99-36x
ex3/ A= 9x*x= 9x²
B = 2x*6x= 12x²
