Question

Find the value of p for which equation x^2+7px+9=0 has no real roots

Answer 1

Given: The equation x^2 + 7px + 9 = 0

To find: The value of p?

Solution:

• Now we have given the equation as: x^2 + 7px + 9 = 0

• The given condition is that equation has no real roots.

• That means discriminant is less than 0.

                   b^2 - 4(a)(c) < 0

• So putting the values in it, we get:

                   (7p)^2 - 4(1)(9) < 0

                   49p^2 - 36 < 0

                   49p^2 < 36

                   p^2 < 36 / 49

                   p < √(36 / 49)

                   p < 6/7

Answer:

          So the value of p is less than 6/7.