developpez chaque expression :A=3 x(2a+8) et B= 2x x(3x-5y) factoriser chaque expression :C=5xd-5x2 et D= 7y +21

A = 3 X 2a + 3 X 8
A = 6a + 24

B = 2x X 3x + 2x X (-5y)
B = 6x au carré - 10xy

[tex]A= 3*(2a+8) = 3*2a + 3*8 = 6a + 24[/tex]
[tex]B= 2x*(3x-5y) = 2x*3x-2x*5y=6x^{2} -10xy[/tex]
[tex]C=5*d-5*2=5(d-2)[/tex]
[tex]D=7y-21=7*y-7*3=7(y-3)[/tex]