A=(4x+9)-(2x-1)
= 4x +9 - 2x -1
= 4x -2x +9 -1
= 2x + 8
B=-4 (6+5x)+9 (2x-3)
= (-4 * 6 -4*5x) +(9*2x + 9 *-3)
= -24 - 20x + 18x - 27
= -20 +18x -24 -27
= -2 x - 51
C=-3a-8-7b-9a-7a-2
= -3a - 9a -7a -7b -8 -2
= -19a -7b -10
D=5(2x-7)-4 (3x-8)
= (5*2x + 5 *-7) - (4*3x + 4 * -8)
= 10x - 35 - (12x - 32)
= 10x - 35 - 12x +32
= 10x -12x -35 +32
= -2x - 3
E=7x(3x-2)-x(6+x)-(5-4x)
= 7x *3x + 7x * -2 - (x *6 + x *x) - 5 -4x
= 21x² - 14x - (6x + x²) -5 -4x
= 21x² -14x - 6x - x² -5 -4x
= 21x² - x² -14x -4x -6x -5
= 20x² - 24x -5
