Try x, x+1, x+2 → x² + (x+1)² + (x+2)² = 3x² + 6x + 5 = 425 → 3x² + 6x = 420 → x² + 2x = 140 → x² + 2x − 140 = 0 → Discriminant = 564, not square.
Try x, x+1, x+2: Deriving the Truth Behind x² + (x+1)² + (x+2)² = 425
Mathematics is full of elegant patterns and clever shortcuts, and one fascinating expression involves squaring three consecutive integers:
x, x+1, x+2
When we square each term and sum them, we get: x² + (x+1)² + (x+2)² = x² + (x² + 2x + 1) + (x² + 4x + 4) Combine like terms: = x² + x² + 2x + 1 + x² + 4x + 4 = 3x² + 6x + 5
This expression surprisingly equals 425, so we set up the equation: 3x² + 6x + 5 = 425
Subtract 425 from both sides to form a standard quadratic equation: 3x² + 6x + 5 − 425 = 0 → 3x² + 6x − 420 = 0
Divide the entire equation by 3 to simplify: x² + 2x − 140 = 0
Now, to solve this quadratic, apply the quadratic formula: x = [−b ± √(b² − 4ac)] / (2a), where a = 1, b = 2, c = −140
Calculate the discriminant: Δ = b² − 4ac = 2² − 4(1)(−140) = 4 + 560 = 564
Since 564 is not a perfect square (√564 ≈ 23.75), the solutions for x are irrational: x = [−2 ± √564] / 2 → x = −1 ± √141
This result reveals an important mathematical insight: while the sums of consecutive squares follow a precise pattern, arriving at a nicer number like 425 leads to a quadratic with no simple integer solutions—only irrational ones.
This example highlights how even simple patterns in algebra can lead to deeper analysis, testing both computational skill and conceptual understanding.
Conclusion: x² + (x+1)² + (x+2)² = 425 simplifies beautifully to 3x² + 6x + 5 = 425, yielding a quadratic equation with an irrational discriminant. This reminds us that not every numerical puzzle has elegant whole-number answers—sometimes the journey reveals as much as the result.
Keywords: x² + (x+1)² + (x+2)² = 425, quadratic equation solution, discriminant 564, irrational roots, algebra pattern, math problem solving
