Question

Write the value of $\lambda$ for which $x^2+4x+\lambda =0$ has equal roots.

Answer 1

$x^2+4x+\gamma =0$

$b^2-4ac=0$

$(4{)}^2-4(1\left)\right(\gamma )=0$

$16-4\gamma =0$

$16=4\gamma$

$\gamma =4.$