If -4 is a root of the quadratic equation x2+px-4=k and the quadratic equation x2+px+k=0 has equal roots. Find the value of k
since -4 is the root of the quadratic equation .......(1)
therefore x=-4 will satisfy the equation (1).
the quadratic equation ........(3)has equal roots.
therefore the discriminant of the equation (3) is equal to zero.
by (2) and (4) :
hope this helps you.