Question

What multiplies to make -10 and adds to make 11?

Answer 1

$xy=-10$
$x+y=11$
Rearrange and substitute
$y=11-x$
$x(11-x)=-10$
$-x^{2} +11x+10=0$
$(-x+10)(x-1)$
$x=1or,x=-10$
substitute 1 and -10 in for x to find y