A = (x+2)(2x+3)
= 2x² + 4x + 3x + 6
= 2x²+7x+6
B = (x-1)(4x+5)
= 4x²+ 5x - 4x -5
= 4x²+ x -5
C = (2x-1)(3x-2)
= 6x²-4x-3x+2
= 6x²-7x+2
A+B = 2x²+7x+6 + 4x² + x - 5
= 6x² + 8x + 1
B+C = 4x² + x -5 + 6x² -7x + 2
= 10x² -6x -3
A-C = 2x² + 7x + 6 -(6x²-7x+2)
= 2x² + 7x + 6 - 6x² + 7x - 2
= -4x² + 14x + 4
