Correct Answer:
A. x² + 4x + 3 = 0
Correct answer: x² + 4x + 3 = 0. The equation is x² − (sum)x + (product) = 0, so x² − (−4)x + 3 = x² + 4x + 3 = 0.
Background: For ax² + bx + c = 0, the sum of roots = −b/a and the product = c/a.
- x² − 4x + 3 = 0: This would have a sum of roots equal to +4.
- x² + 4x − 3 = 0: This would have a product of −3.
- x² + 4x + 3 = 1: This is not a standard-form equation for the given roots.
Did you know? The roots here are −1 and −3.
Memory trick: x² − (sum)x + product.