Chapter 5 Polynomials and Polynomial Functions - 5.6 Find Rational Zeroes - 5.6 Exercises - Mixed Review - Page 377: 63

The discriminant is $0$. So the equation has only one solution and that solution is real.

The given equation is $s^2-14s+49=0$. The discriminant of the quadratic equation $as^2+bs+c=0$ is $b^2-4ac$. Here $a=1, b=-14, c=49$ $b^2-4ac=(-14)^2-4(1)(49)$ Discriminant $=196-196$ Discriminant $=0$ Since the discriminant is $0$, the equation has only one solution and that solution is real.