∫Calc Practice

Planes: distances and angles

Problem 9.813 · easy

Find an equation of the plane through \( \displaystyle (-3, -3, 3) \) with normal vector \( \displaystyle \left\langle 4, 3, -2 \right\rangle \).
  1. n · (r − P) = 0, i.e. ax + by + cz = n · P.
    Reviewed
  2. \[ 4 \left(-3\right) + 3 \left(-3\right) - 2 \cdot 3 = -27 \]
    n · P.✓ Proved
Answer \( 4 x + 3 y - 2 z = -27 \)

✓ Nihil obstat Lines: 1 proved, 1 reviewed. The answer was also checked a second way, without looking at the solution. Reviewers found nothing wrong with the explanation. How we verify

The full receipt
LineStatusChecked byDetail
1Reviewedreviewers: gpt-oss:20b, qwen3.6:27b-mlxa sentence; read, not computed
2✓ Provedsympy 1.14.0simplify(lhs - rhs) reduced to 0
answer, a second way✓ Checked independentlysympy 1.14.0 + mpmath 1.3.0the plane holds P and its gradient is parallel to n

Reviewers

  • gpt-oss:20b: pass
  • qwen3.6:27b-mlx: pass — The solution correctly applies the point-normal form of the plane equation and accurately computes the constant term.
Every verdict on record (6)
  • qwen3.6:27b-mlx: pass 2026-10-19 — The solution correctly applies the point-normal form of the plane equation and accurately computes the constant term.
  • gpt-oss:20b: pass 2026-10-19
  • qwen3.6:27b-mlx: pass 2026-10-18 — The solution correctly identifies the scalar equation of a plane using the normal vector and a point, and the arithmetic for the constant term is correct.
  • gpt-oss:20b: pass 2026-10-18
  • qwen3.6:27b-mlx: pass 2026-10-18 — The solution correctly applies the point-normal form of the plane equation and accurately computes the constant term.
  • gpt-oss:20b: pass 2026-10-18

Proved: SymPy reduced the difference between the two sides to zero. Checked independently: a separate method, named above, confirmed it. Checked numerically: the two sides agree at every sampled point, which is evidence, not proof. Reviewed: a model or a person read it; that is all a sentence can have. Solution by generator:structured/planes_distance_angle, checked 2026-10-19 with SymPy 1.14.0.