Which of the following equations has only one solution? x2 + 4x + 4 = 0 x2 + x = 0 x2 - 1 = 0

The correct equation is

Step-by-step explanation: We are given to select the quadratic equation that has only one solution.

We know that - for the quadratic equation the type of solution can be determined by the discriminant as follows :

(i) If D > 0, then the equation will have two distinct real solutions.

(ii) If D < 0, then the equation will have two distinct complex solutions.

(ii) If D = 0, then there is only one real solution.

(A) The first equation is

Here, a = 1, b = 4 and c = 4.

So, the discriminant is given by

Therefore, the equation will have only one real solution.

(B) The second equation is

Here, a = 1, b = 1 and c = 0.

So, the discriminant is given by

Therefore, the equation will have two distinct real solutions.

(C) The third equation is

Here, a = 1, b = -1 and c = 0.

So, the discriminant is given by

Therefore, the equation will have two distinct real solutions.

Thus, is the correct equation.

a box 3 3/4 feet long or 4+ feet.

step-by-step explanation: