Bonsoir,
Développer:
[tex]A=(2x-5)(3x-6)+(2x-5)\times4\\
A=2x\times 3x+2x\times (-6)-5\times 3x-5\times (-6)+2x\times 4-5\times4\\
A = 6x^2-12x-15x+30+8x-20\\
A = 6x^2-12x-15x+8x+30-20\\
\boxed{A = 6x^2-19x+10}[/tex]
Factoriser A:
[tex]A=(2x-5)(3x-6)+(2x-5)\times4\\
A = (2x-5)(3x-6+4)\\
\boxed{A = (2x-5)(3x-2)}[/tex]
Factoriser B:
[tex]B = (4x+3)(2x+5)-5(4x+3)\\B = (4x+3)(2x+5-5)\\
B = (4x+3)(2x)\\
\boxed{B = 2x\times(4x+3)}[/tex]
