For what values of x is x2 + 2x = 24 true?

–6 and –4
–4 and 6
4 and –6
6 and 4

1 answer

To solve the equation \(x^2 + 2x = 24\), we first rearrange it to standard quadratic form:

\[ x^2 + 2x - 24 = 0 \]

Next, we can factor the quadratic equation. We need to find two numbers that multiply to \(-24\) (the constant term) and add to \(2\) (the coefficient of the linear term).

The numbers \(6\) and \(-4\) work because:

\[ 6 \times (-4) = -24 \] \[ 6 + (-4) = 2 \]

Thus, we can factor the equation as:

\[ (x + 6)(x - 4) = 0 \]

Setting each factor equal to zero gives us the possible values for \(x\):

  1. \(x + 6 = 0\) implies \(x = -6\)
  2. \(x - 4 = 0\) implies \(x = 4\)

Therefore, the solutions to the equation \(x^2 + 2x = 24\) are:

\[ x = -6 \quad \text{and} \quad x = 4 \]

In terms of the answer choices provided, the correct one is:

–6 and 4.