Question

x^2+10x
factor completely
$x {}^{2} + 10$

Answer 1

$x^2+10x=x(x+10)\\--------------------\\\\x^2+10=x^2-(-10)=x^2-(i\sqrt{10})^2\\\\\text{use}\ a^2-b^2=(a-b)(a+b)\\\\=(x-i\sqrt{10})(x+i\sqrt{10})$