a= (2x+3)(3x-5)+(2x+3)(x-7) develloper et reduire a factoriser a calculer pour x= 2 urgent pour mercredi j'ai pas compris merci

A = (2x + 3)(3x - 5) + (2x + 3)(x - 7)
A = 6x² - 10x + 9x - 15 + 2x² -14x + 3x - 21
A = 8x² - 12x - 36 ;

A = (2x + 3)(3x - 5 + x -7)
A = (2x + 3)(4x - 12) ;

A = (2x2 + 3)(4x2 - 12) = 7 x (-4) = - 28 .

a=(2x+3)(3x-5)+(2x+3)(x-7)
=6x*2-10x+9x-15 + 2x*2-14x+3x-21
=6x*2+2x*2-10x+9x-14x+3x-15-21
=8x*2-x-11x-36
=8x*2-12x-36
a=(2x+3)(3x-5+x-7)
=(2x+3)(4x-12)
=2X2+3 +4X2-12
=4+3 X 8-12
=7X-4
=-28
=