Sagot :
= (2x-5)(x+7)-(x+9)(7x-2)
= (2x2+14x-5x+35)-(7x2-2x+63x+18)
= 2x2+9x+35-7x2-61x+18
= 9x2 - 52x + 53
A= (2x-5)(x+7)-(x+9)(7x-2)
A= (2x2+14x-5x+35)-(7x2-2x+63x+18)
A= 2x2+9x+35-7x2-61x+18
A= 9x2 - 52x + 53
= (2x-5)(x+7)-(x+9)(7x-2)
= (2x2+14x-5x+35)-(7x2-2x+63x+18)
= 2x2+9x+35-7x2-61x+18
= 9x2 - 52x + 53
A= (2x-5)(x+7)-(x+9)(7x-2)
A= (2x2+14x-5x+35)-(7x2-2x+63x+18)
A= 2x2+9x+35-7x2-61x+18
A= 9x2 - 52x + 53