$\,-2\;(\,-9\,-8\,a) = $   ?

$\,18 +\,8\,\,a$ $\,18 \,-10\,a$ $\,-11 \,-10\,\,a$ $\,18 +\,16\,\,a$ $\,18 \,-8\,a$ $\,18 \,-16\,\,a$

$\,-2\,y\;(\,5\,x\,-9) = $   ?

$\,-10\,\,x\,y \,-11$ $\,-10\,\,x\,y +\,18\,\,y$ $\,-10\,\,x\,y \,-18$ $\,3\,\,x\,y \,-11\,\,y$ $\,10\,\,x\,y +\,18$ $\,-10\,\,x\,y \,-9$

$\,3\,x\;(\,-4\,x+\,8\,y) = $   ?

$\,-12\,\,x^2 +\,11\,\,x\,y$ $\,-12\,\,x^2 \,-24\,y$ $\,-12\,\,x^2 +\,24\,\,x\,y$ $\,-12\,\,x^2 +\,8\,y$ $\,12\,\,x^2 +\,24\,y$ $\,-\,\,x^2 +\,11\,\,x\,y$

$\,5\,x\;(\,-7\,x\,-5\,y) = $   ?

$\,-2\,\,x^2 $ $\,-35\,\,x^2 $ $\,-35\,\,x^2 \,-5\,y$ $\,-35\,\,x^2 \,-25\,\,x\,y$ $\,35\,\,x^2 \,-25\,y$ $\,-35\,\,x^2 +\,25\,y$

$(\,3+\,t)\;(\,-1+\,4\,t) = $   ?

$\,4\,\,t^2 +\,11\,\,t +\,3$ $\,4\,\,t^2 +\,11\,\,t \,-3$ $\,4\,\,t^2 +\,13\,\,t \,-3$ $\,4\,\,t^2 \,-13\,\,t +\,3$

$(\,b\,-1)\;(\,-\,a\,-6) = $   ?

$\,-\,\,a\,b +\,6\,\,b \,-\,\,a +\,6$ $\,-\,\,a\,b \,-6\,\,b \,-\,\,a \,-6$ $\,-\,\,a\,b \,-6\,\,b +\,\,a +\,6$ $\,-\,\,a\,b \,-6\,\,b +\,\,a \,-6$

$(\,4\,-\,b)\;(\,-\,b+\,5) = $   ?

$\,-\,\,b^2 +\,\,b +\,20$ $\,\,b^2 \,-9\,\,b +\,20$ $\,\,b^2 +\,\,b \,-20$ $\,\,b^2 \,-\,\,b \,-20$

Quelle est l'expression factorisée de $\,5\,\,y^2\;+\,3\,\,y$ ?

$\,y\;(\,5\;+\,3\,y)$ $\,y\;(\,5\,^{2}\;+\,3)$ $\,y\;(\,5\,y\;+\,2)$ $\,y\;(\,5\,y\;+\,3)$

Quelle est l'expression factorisée de $\,-48\;+\,42\,\,y$ ?

$\,6\;(\,8\;+\,7\,y)$ $\,6\;(\,-8\;+\,y)$ $\,6\;(\,-8\;+\,7\,y)$ $\,6\;(\,-8\;+\,42\,y)$

Quelle est l'expression factorisée de $\,-56\,\,t\,y\;+\,63\,\,t^2$ ?

$\,7\,t\;(\,-8\,y\;+\,t)$ $\,7\,t\;(\,-8\,y\;+\,9\,^{2})$ $\,7\,t\;(\,-8\,y\;+\,9\,t)$ $\,7\,t\;(\,8\,y\;\,-9\,t)$