1. Consider the polynomial \( ax^2 + bx - c \).
2. We need to factor it into binomials: \( (px + q)(rx + s) \).
3. Expanding the binomials:
(px + q)(rx + s) = prx^2 + (ps + qr)x + qs
4. Match the coefficients with the original polynomial:
a = pr, \quad b = ps + qr, \quad c = -qs
5. Since \( a \), \( b \), and \( c \) are positive, we need \( a \) and \( b \) terms to be positive while \( c \) is negative.
6. To satisfy these conditions, one binomial should have a positive constant, and the other should have a negative constant. Therefore, the signs in the binomials must be one positive and one negative.
Example:
1. Let's take \( 2x^2 + 3x - 4 \):
2. Factor it as \( (2x - 1)(x + 4) \):
3. Expand to verify:
(2x - 1)(x + 4) = 2x^2 + 8x - x - 4 = 2x^2 + 7x - 4
4. Verification shows it doesn't match \( 2x^2 + 3x - 4 \), let’s try another factor pair.
5. Factor it as \( (2x + 4)(x - 1) \):
(2x + 4)(x - 1) = 2x^2 - 2x + 4x - 4 = 2x^2 + 2x - 4
Again, try with different factor pairs \( (2x + 4)(x - 1) \)
[Step-by-Step Solution] One binomial's SIGN is positive and another is negative, final binomials for actual verification.