Lines and slopes
Problem 13.310 · easy
Find the equation of the line with slope \( \displaystyle - \frac{3}{2} \) through \( \displaystyle (5, 2) \), in slope-intercept form.
- \[ 2 - \frac{3 \left(x - 5\right)}{2} = \frac{19}{2} - \frac{3 x}{2} \]Point-slope form, then simplify.✓ Proved
- \[ \left. - \frac{3 x}{2} + \frac{19}{2} \right|_{\substack{ x=5 }} = 2 \]The line passes through (5, 2).✓ Proved
Answer \( y = \frac{19}{2} - \frac{3 x}{2} \)
Every line of this solution was proved by the computer algebra system SymPy. The answer was also checked a second way, without looking at the solution. The reviewers disagree about how one step is explained; every verdict is in the receipt. How we verify
The full receipt
| Line | Status | Checked by | Detail |
|---|---|---|---|
| 1 | ✓ Proved | sympy 1.14.0 | simplify(lhs - rhs) reduced to 0 |
| 2 | ✓ Proved | sympy 1.14.0 | simplify(lhs - rhs) reduced to 0 |
| answer, a second way | ✓ Checked independently | sympy 1.14.0 + mpmath 1.3.0 | the line meets the point with the required slope |
Reviewers
gpt-oss:20b: passqwen3.6:27b-mlx: fail (error) — The solution fails to explicitly state the point-slope formula or the substitution step used to derive the equation. It presents an algebraic identity and a verification check without showing the logical derivation from the given slope and point to the final slope-intercept form.
Every verdict on record (6)
qwen3.6:27b-mlx: fail (error) 2026-10-18 — The solution fails to explicitly state the point-slope formula or the substitution step used to derive the equation. It presents an algebraic identity and a verification check without showing the logical derivation from the given slope and point to the final slope-intercept form.gpt-oss:20b: pass 2026-10-18qwen3.6:27b-mlx: pass 2026-10-16 — The solution correctly derives the slope-intercept form and verifies the point. The steps are algebraically sound and logically complete.gpt-oss:20b: pass 2026-10-16qwen3.6:27b-mlx: fail (error) 2026-10-15 — The solution provides no derivation or explanation of how the slope-intercept form was obtained from the given point and slope. It merely verifies the final answer algebraically, failing to demonstrate the required method (using y - y1 = m(x - x1)).gpt-oss:20b: pass 2026-10-15
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/lines_slopes, checked 2026-10-18 with SymPy 1.14.0.