Question

If -5 is aroot of 2x^2-px-15 and the quadratic equation p(x^2+x)+k=0 has equal roots then find the value of K.

Answer 1

the value of p is -7
the value of k is -7/4

Answer 2

-5 is root of 2xsq-px-15
putting the value of x=-5
2×-5×-5-(p×-5)-15=0
50+5p-15=0
p=-35/5
p=-7
now
-7×(x^2+x)+k=0
-7xsq-7x+k=0
for equal root
d=0
b^2-4ac=0
49+28k=0
k=49/28
k=7/4