Question

If one of the factor of $x^2+x-20$ is $(x+5)$, find other factor

• A. $(x+4)$
• B. $(x-4)$
  
• C. $(x-2)$
• D. $(x+2)$

Answer 1

The correct option is B $(x-4)$

Since, $x+5$ is factor of $x^2+x-20$,
Therefore,
$x+5)\overline{x^2+x-20}$( $x-4$
$\underset{–}{{\underset{-}{x}}^2\underset{-}{+}5x}$
$-4x-20$
$\underset{–}{\underset{+}{-}4x\underset{+}{-}20}$
$0$
Therefore, the other factor is $x-4$