$(\,6+\,6\,b)\;(\,5+\,a) = $   ?

$\,30 +\,6\,\,a +\,30\,\,b +\,6\,\,a\,b$ $\,11 +\,7\,\,a +\,11\,\,b +\,7\,\,a\,b$ $\,42\,\,a^2\,b^2 +\,30$ $\,6\,\,a\,b +\,30$

$(\,2+\,4\,y)\;(\,6+\,y) = $   ?

$\,4\,\,y^2 +\,26\,\,y +\,12$ $\,4\,\,y^2 +\,12$ $\,5\,\,y^2 +\,13\,\,y +\,8$ $\,30\,\,y +\,12$

$(\,b+\,2)\;(\,4+\,3\,a) = $   ?

$\,5\,\,b +\,4\,\,a\,b +\,6 +\,5\,\,a$ $\,3\,\,a\,b +\,8$ $\,13\,\,a^2\,b^2 +\,8$ $\,4\,\,b +\,3\,\,a\,b +\,8 +\,6\,\,a$

$(\,5+\,y)\;(\,4+\,5\,y) = $   ?

$\,34\,\,y +\,20$ $\,6\,\,y^2 +\,15\,\,y +\,9$ $\,5\,\,y^2 +\,20$ $\,5\,\,y^2 +\,29\,\,y +\,20$

$(\,5+\,x)\;(\,-3\,y+\,2) = $   ?

$\,-15\,\,y +\,10 \,-3\,\,x\,y +\,2\,\,x$ $\,-15\,\,y \,-10 \,-3\,\,x\,y +\,2\,\,x$ $\,15\,\,y +\,10 +\,3\,\,x\,y +\,2\,\,x$ $\,-15\,\,y +\,10 \,-3\,\,x\,y \,-2\,\,x$

$(\,1\,-4\,y)\;(\,2\,x\,-1) = $   ?

$\,2\,\,x \,-1 \,-8\,\,x\,y +\,4\,\,y$ $\,-2\,\,x \,-1 \,-8\,\,x\,y \,-4\,\,y$ $\,-2\,\,x \,-1 +\,8\,\,x\,y +\,4\,\,y$ $\,2\,\,x \,-1 \,-8\,\,x\,y \,-4\,\,y$

$(\,5\,t+\,3)\;(\,6\,t\,-4) = $   ?

$\,30\,\,t^2 \,-38\,\,t \,-12$ $\,30\,\,t^2 \,-2\,\,t \,-12$ $\,-30\,\,t^2 \,-38\,\,t \,-12$ $\,30\,\,t^2 +\,38\,\,t \,-12$

$(\,x\,-6)\;(\,-3\,-4\,y) = $   ?

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

$(\,b\,-1)\;(\,2\,b\,-6) = $   ?

$\,2\,\,b^2 \,-4\,\,b +\,6$ $\,-2\,\,b^2 +\,4\,\,b +\,6$ $\,2\,\,b^2 \,-8\,\,b +\,6$ $\,2\,\,b^2 +\,4\,\,b +\,6$

$(\,6\,-2\,b)\;(\,-4\,-\,b) = $   ?

$\,2\,\,b^2 +\,2\,\,b +\,24$ $\,2\,\,b^2 \,-2\,\,b \,-24$ $\,2\,\,b^2 +\,2\,\,b \,-24$ $\,2\,\,b^2 +\,14\,\,b \,-24$