x^2-4x-21

Question

your gonna make me fail so factor good

Answer 1

To factor the quadratic expression \(x^2 - 4x - 21\), we need to find two numbers that multiply to \(-21\) (the constant term) and add up to \(-4\) (the coefficient of the linear term).

The numbers \(-7\) and \(3\) work because:

\[ -7 \times 3 = -21 \] and \[ -7 + 3 = -4. \]

Now we can write the factored form of the expression:

\[ x^2 - 4x - 21 = (x - 7)(x + 3). \]

So, the factored form is:

\[ \boxed{(x - 7)(x + 3)}. \]