Question

1. If $8$ is the root of the equation $x^2-10x+k=0,$ then find the value of $k.$

Answer 1

$x^2-10x+k=0$

$\alpha +\beta =10$

$⟹\alpha +8=10$

$⟹\alpha =2$

$\alpha \beta =k$

$⟹8\times 2=k$

$⟹k=16$