$(\,t+\,6)\;(\,2+\,5\,x) = $   ?

$\,3\,\,t +\,6\,\,t\,x +\,8 +\,11\,\,x$ $\,2\,\,t +\,5\,\,t\,x +\,12 +\,30\,\,x$ $\,37\,\,t^2\,x^2 +\,12$ $\,5\,\,t\,x +\,12$

$(\,x+\,5)\;(\,x+\,3) = $   ?

$\,9\,\,x +\,15$ $\,\,x^2 +\,15$ $\,2\,\,x^2 +\,10\,\,x +\,8$ $\,\,x^2 +\,8\,\,x +\,15$

$(\,2\,a+\,4)\;(\,3\,b+\,6) = $   ?

$\,6\,\,a\,b +\,24$ $\,30\,\,a^2\,b^2 +\,24$ $\,5\,\,a\,b +\,8\,\,a +\,7\,\,b +\,10$ $\,6\,\,a\,b +\,12\,\,a +\,12\,\,b +\,24$

$(\,y+\,1)\;(\,2+\,4\,y) = $   ?

$\,4\,\,y^2 +\,2$ $\,10\,\,y +\,2$ $\,5\,\,y^2 +\,8\,\,y +\,3$ $\,4\,\,y^2 +\,6\,\,y +\,2$

$(\,1\,-3\,b)\;(\,3+\,a) = $   ?

$\,3 +\,\,a +\,9\,\,b \,-3\,\,a\,b$ $\,-3 +\,\,a +\,9\,\,b \,-3\,\,a\,b$ $\,3 +\,\,a \,-9\,\,b \,-3\,\,a\,b$ $\,3 \,-\,\,a \,-9\,\,b +\,3\,\,a\,b$

$(\,t\,-6)\;(\,4\,x\,-3) = $   ?

$\,4\,\,t\,x +\,3\,\,t +\,24\,\,x +\,18$ $\,4\,\,t\,x \,-3\,\,t +\,24\,\,x +\,18$ $\,4\,\,t\,x \,-3\,\,t \,-24\,\,x +\,18$ $\,4\,\,t\,x +\,3\,\,t \,-24\,\,x +\,18$

$(\,2+\,5\,y)\;(\,-4+\,6\,y) = $   ?

$\,-30\,\,y^2 \,-8\,\,y +\,8$ $\,30\,\,y^2 +\,32\,\,y \,-8$ $\,30\,\,y^2 +\,32\,\,y +\,8$ $\,30\,\,y^2 \,-8\,\,y \,-8$

$(\,6\,-6\,y)\;(\,-\,x\,-4) = $   ?

$\,6\,\,x \,-24 +\,6\,\,x\,y +\,24\,\,y$ $\,6\,\,x +\,24 +\,6\,\,x\,y +\,24\,\,y$ $\,-6\,\,x +\,24 +\,6\,\,x\,y \,-24\,\,y$ $\,-6\,\,x \,-24 +\,6\,\,x\,y +\,24\,\,y$

$(\,5\,y\,-4)\;(\,y\,-1) = $   ?

$\,5\,\,y^2 \,-9\,\,y +\,4$ $\,5\,\,y^2 +\,9\,\,y +\,4$ $\,5\,\,y^2 \,-\,\,y +\,4$ $\,5\,\,y^2 +\,\,y +\,4$

$(\,5\,-\,x)\;(\,-\,x\,-4) = $   ?

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