$\,-3\;(\,2\,b\,-4) = $   ?

$\,-6\,\,b \,-12$ $\,-6\,\,b +\,4$ $\,-\,\,b \,-7$ $\,-6\,\,b \,-7$ $\,-6\,\,b +\,12$ $\,-6\,\,b \,-4$

$\,-2\,x\;(\,-3\,-7\,y) = $   ?

$\,-6\,\,x +\,14\,y$ $\,6\,\,x \,-7\,y$ $\,-5\,\,x \,-9\,\,x\,y$ $\,6\,\,x \,-14\,y$ $\,6\,\,x \,-9\,y$ $\,6\,\,x +\,14\,\,x\,y$

$\,4\,y\;(\,-\,y+\,7\,x) = $   ?

$\,3\,\,y^2 +\,11\,\,x\,y$ $\,-4\,y +\,28\,\,x\,y$ $\,-4\,\,y^2 \,-28\,x$ $\,4\,\,y^2 +\,11\,\,x\,y$ $\,-4\,\,y^2 +\,28\,\,x\,y$ $\,-4\,\,y^2 +\,7\,x$

$\,6\,t\;(\,9\,t+\,5\,x) = $   ?

$\,-54\,\,t^2 +\,11\,\,t\,x$ $\,54\,\,t^2 +\,30\,\,t\,x$ $\,54\,\,t^2 +\,30\,x$ $\,54\,\,t^2 \,-30\,x$ $\,54\,\,t^2 +\,5\,x$ $\,15\,\,t^2 +\,11\,\,t\,x$

$(\,3\,t\,-5)\;(\,5+\,4\,t) = $   ?

$\,-12\,\,t^2 \,-5\,\,t +\,25$ $\,-12\,\,t^2 \,-35\,\,t \,-25$ $\,12\,\,t^2 \,-5\,\,t \,-25$ $\,12\,\,t^2 +\,35\,\,t +\,25$

$(\,3\,x\,-4)\;(\,-5\,-\,y) = $   ?

$\,-15\,\,x \,-3\,\,x\,y +\,20 +\,4\,\,y$ $\,-15\,\,x \,-3\,\,x\,y \,-20 +\,4\,\,y$ $\,-15\,\,x \,-3\,\,x\,y +\,20 \,-4\,\,y$ $\,15\,\,x \,-3\,\,x\,y +\,20 \,-4\,\,y$

$(\,2\,-\,y)\;(\,4\,-6\,y) = $   ?

$\,-6\,\,y^2 \,-16\,\,y \,-8$ $\,6\,\,y^2 +\,16\,\,y +\,8$ $\,6\,\,y^2 \,-16\,\,y +\,8$ $\,-6\,\,y^2 \,-8\,\,y +\,8$

Quelle est l'expression factorisée de $\,8\,\,a\;+\,3\,\,a^2$ ?

$\,a\;(\,8\;+\,a)$ $\,a\;(\,8\;+\,3\,^{2})$ $\,a\;(\,8\;+\,3\,a)$ $\,a\;(\,8\,a\;+\,3)$

Quelle est l'expression factorisée de $\,25\;\,-40\,\,t$ ?

$\,5\;(\,-5\;+\,8\,t)$ $\,5\;(\,5\,t\;\,-40)$ $\,5\;(\,5\;\,-8\,t)$ $\,5\;(\,5\;\,-40\,t)$

Quelle est l'expression factorisée de $\,-24\,\,t\,y\;+\,21\,\,t^2$ ?

$\,3\,t\;(\,-8\,y\;+\,21\,t)$ $\,3\,t\;(\,-8\,y\;+\,7\,t)$ $\,3\,\,t^2\;(\,-8\,y\;+\,7)$ $\,3\,t\;(\,-8\,y\;+\,7\,^{2})$