$(\,5+\,6\,y)\;(\,x+\,4) = $   ?

$\,6\,\,x\,y +\,20$ $\,5\,\,x +\,20 +\,6\,\,x\,y +\,24\,\,y$ $\,6\,\,x +\,9 +\,7\,\,x\,y +\,10\,\,y$ $\,35\,\,x^2\,y^2 +\,20$

$(\,4\,y+\,6)\;(\,6\,y+\,1) = $   ?

$\,64\,\,y +\,6$ $\,10\,\,y^2 +\,17\,\,y +\,7$ $\,24\,\,y^2 +\,6$ $\,24\,\,y^2 +\,40\,\,y +\,6$

$(\,4\,y+\,4)\;(\,3+\,x) = $   ?

$\,20\,\,x^2\,y^2 +\,12$ $\,4\,\,x\,y +\,12$ $\,7\,\,y +\,5\,\,x\,y +\,7 +\,5\,\,x$ $\,12\,\,y +\,4\,\,x\,y +\,12 +\,4\,\,x$

$(\,4+\,y)\;(\,1+\,6\,y) = $   ?

$\,31\,\,y +\,4$ $\,6\,\,y^2 +\,25\,\,y +\,4$ $\,7\,\,y^2 +\,12\,\,y +\,5$ $\,6\,\,y^2 +\,4$

$(\,b+\,3)\;(\,4\,a\,-2) = $   ?

$\,4\,\,a\,b \,-2\,\,b +\,12\,\,a \,-6$ $\,4\,\,a\,b \,-2\,\,b \,-12\,\,a +\,6$ $\,4\,\,a\,b +\,2\,\,b \,-12\,\,a \,-6$ $\,-4\,\,a\,b \,-2\,\,b \,-12\,\,a \,-6$

$(\,2\,b\,-5)\;(\,-4\,a+\,3) = $   ?

$\,8\,\,a\,b +\,6\,\,b +\,20\,\,a \,-15$ $\,8\,\,a\,b +\,6\,\,b +\,20\,\,a +\,15$ $\,-8\,\,a\,b +\,6\,\,b +\,20\,\,a \,-15$ $\,-8\,\,a\,b +\,6\,\,b +\,20\,\,a +\,15$

$(\,3\,-6\,b)\;(\,b+\,4) = $   ?

$\,-6\,\,b^2 \,-21\,\,b +\,12$ $\,-6\,\,b^2 +\,27\,\,b +\,12$ $\,6\,\,b^2 \,-27\,\,b +\,12$ $\,6\,\,b^2 \,-21\,\,b +\,12$

$(\,4\,-\,a)\;(\,-6\,b\,-3) = $   ?

$\,24\,\,b \,-12 \,-6\,\,a\,b +\,3\,\,a$ $\,-24\,\,b \,-12 +\,6\,\,a\,b +\,3\,\,a$ $\,24\,\,b \,-12 +\,6\,\,a\,b +\,3\,\,a$ $\,-24\,\,b +\,12 +\,6\,\,a\,b +\,3\,\,a$

$(\,6+\,6\,t)\;(\,-3\,-2\,t) = $   ?

$\,12\,\,t^2 \,-30\,\,t +\,18$ $\,-12\,\,t^2 +\,6\,\,t \,-18$ $\,-12\,\,t^2 \,-30\,\,t \,-18$ $\,-12\,\,t^2 \,-30\,\,t +\,18$

$(\,4\,-\,x)\;(\,-2\,-6\,x) = $   ?

$\,6\,\,x^2 \,-22\,\,x \,-8$ $\,6\,\,x^2 +\,26\,\,x +\,8$ $\,6\,\,x^2 \,-22\,\,x +\,8$ $\,6\,\,x^2 \,-26\,\,x +\,8$