Use the discriminant to determine the number of real solutions of x2+14x+24=0

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1 answer

To determine the number of real solutions of the quadratic equation \(x^2 + 14x + 24 = 0\), we first need to calculate the discriminant, which is given by the formula:

\[ D = b^2 - 4ac \]

In this equation, the coefficients are:

  • \(a = 1\)
  • \(b = 14\)
  • \(c = 24\)

Now, substituting these values into the discriminant formula:

\[ D = 14^2 - 4 \cdot 1 \cdot 24 \]

Calculating \(14^2\):

\[ 14^2 = 196 \]

Now calculating \(4 \cdot 1 \cdot 24\):

\[ 4 \cdot 1 \cdot 24 = 96 \]

Now, substituting these values into the discriminant:

\[ D = 196 - 96 = 100 \]

Now we analyze the value of the discriminant \(D\):

  • If \(D > 0\), there are two distinct real solutions.
  • If \(D = 0\), there is exactly one real solution (a repeated root).
  • If \(D < 0\), there are no real solutions.

Since \(D = 100\) which is greater than 0, we conclude that the quadratic equation \(x^2 + 14x + 24 = 0\) has two distinct real solutions.