Mathematics for IGCSE & O level - Algebraic Manipulation (Section 1 - No. 23)
If 'c' is negative in a quadratic expression, what can you say about the signs of the numbers you seek to factor the expression?
Both will be positive.
Both will be negative.
They will be the same sign.
They will have opposite signs.
解释
To result in a negative constant, one factor must be positive, and the other negative.