Question

Determine whether the values given against each of the quadratic equation are the roots of the equation.
$x^2+4x-5=0,x=1,-1$

Answer 1

$x^2+4x-5=0$

given values of x$=1,-1$

when $x=1\to 1^2+4\left(1\right)-5=1+4-5=0$ satisfies the equation.

when $x=-1\to (-1{)}^2+4(-1)-5=1-4-5=-8$ does not satisfy the equation.

Therefore $x=1$ is only the root of given equation.