Which of the following equations has equal roots?

A quadratic equation : $$ax^2 + bx + c = 0$$ has equal roots iff Discriminant, $$D = b^2 - 4ac = 0$$

(A) : $$x^{2} - 13x + 22 = 0$$

=> D = $$(-13)^2 - 4(1)(22) = 169 - 88 = 81 \neq 0$$

(B) : $$x^{2}- 7x + 10 = 0$$

=> D = $$(-7)^2 - 4(1)(10) = 49 - 40 = 9 \neq 0$$

(C) : $$x^{2}- 2x + 26 = 0$$

=> D = $$(-2)^2 - 4(1)(26) = 4 - 104 = -100 \neq 0$$

(D) : $$x^{2} + 8x + 16 = 0$$

=> D = $$(8)^2 - 4(1)(16) = 64 - 64 = 0$$

Thus, the equation : $$x^{2} + 8x + 16 = 0$$ has equal roots.

=> Ans - (D)