To factor the quadratic expression \( x^2 - x - 72 \), we need to find two numbers that multiply to \(-72\) (the constant term) and add to \(-1\) (the coefficient of the middle term).
After checking the pairs of factors of \(-72\), we find:
- \(8\) and \(-9\) (since \(8 \cdot -9 = -72\) and \(8 + (-9) = -1\)).
Therefore, we can factor the expression as follows:
\[ x^2 - x - 72 = (x + 8)(x - 9) \]
So, the factored form of \( x^2 - x - 72 \) is:
\[ (x + 8)(x - 9) \]
1 answer