# Question 32938: Solution Classification of a Linear System

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This teaching derivation has second-context AI mathematical and bilingual semantic review, limited to the model and assumptions stated in this question. It has no human review or new Lean proof and does not promote the original question or MKO to Canonical truth.

R0064-32938 · q-20261003-advance-20261004-r06-system-linear-equations-0038



## Original question and givens

Over the reals, the constraints (1)x+(6)y=8 and (2)x+(12)y=16 must both hold. Classify the system as no solution, a unique solution, or infinitely many solutions. Zero-coefficient rows are allowed.


- G001 — Over the reals, the constraints (1)x+(6)y=8 and (2)x+(12)y=16 must both hold. Classify the system as no solution, a unique solution, or infinitely many solutions. Zero-coefficient rows are allowed.





## Definition and scope

Use the original question domain, assumptions and cited MKO definitions. This item has second-context mathematical and bilingual review, with the model, answer and every arithmetic step independently recomputed from the original parameters; the source question remains a candidate.


- [mko-system-linear-equations](https://ocme.evemisslab.com/en/mko/mko-system-linear-equations/)





## Step-by-step derivation

S001 · impliesBefore

source roles = [qf-linear-system-solution-class, solution_class, reals, []]

After

derived = [[SOURCE_solution_class_STRING]]

Conditions: none

Legacy banks enforce their exact source keys/operation/domain.BASE integers retain metadata without treating it as an oracle.Distinguish NUMBER,string,fraction pair and vector equality formats;retain original bilingual data/AST/status.

Step identifiers and dependenciesRule: R64_SOURCE_exact_legacy_interface_BASE_metadata_AND_output_roles · Uses: G001





S002 · impliesBefore

source roles = [[[1, 6, 8], [2, 12, 16]]]

After

derived = [[coefficient_x, coefficient_y, right_side]]

Conditions: none

Each ORIGINAL row[a,b,c]means ax+by=c;the THIRD column is RHS,not a coefficient.Type ALL SIX raw SAFE values,including unused RHS in a determinant task.Keep original row order.

Step identifiers and dependenciesRule: System_RAW_exact2_augmented_rows3_ALL_SAFEincl_unused_rhs · Uses: G001, S001





S003 · calculationBefore

System ORIGINAL a times e main product := mul(1, 12)

After

System ORIGINAL a times e main product = 12

Conditions: none

Use ORIGINAL operands/order for exact integer/rational arithmetic.RAW bounds are bank-specific;derived values are not SAFE-recapped or approximated.Do not import legacy caps into BASE integers.

Step identifiers and dependenciesRule: exact_rational_arithmetic · Uses: G001, S002





S004 · calculationBefore

System ORIGINAL b times d other product := mul(6, 2)

After

System ORIGINAL b times d other product = 12

Conditions: none

Use ORIGINAL operands/order for exact integer/rational arithmetic.RAW bounds are bank-specific;derived values are not SAFE-recapped or approximated.Do not import legacy caps into BASE integers.

Step identifiers and dependenciesRule: exact_rational_arithmetic · Uses: G001, S003





S005 · calculationBefore

System ORIGINAL signed determinant ae minus bd := sub(12, 12)

After

System ORIGINAL signed determinant ae minus bd = 0

Conditions: none

Use ORIGINAL operands/order for exact integer/rational arithmetic.RAW bounds are bank-specific;derived values are not SAFE-recapped or approximated.Do not import legacy caps into BASE integers.

Step identifiers and dependenciesRule: exact_rational_arithmetic · Uses: G001, S004





S006 · impliesBefore

source roles = [[[1, 6, 8], [2, 12, 16]]]

After

derived = [12, 12, 0]

Conditions: none

D=ae−bd uses ONLY the first TWO columns,retaining ORIGINAL row order/sign.RHS is excluded;swapping rows changes the sign.Do not replace originals by semantic sorting.

Step identifiers and dependenciesRule: System_DETERMINANT_coefficients_ONLY_raw_order_sign · Uses: G001, S005





S007 · impliesBefore

source roles = [[[1, 6, 8], [2, 12, 16]], 0]

After

derived = [[]]

Conditions: none

At D0,FIRST detect any0x+0y=nonzero contradiction.Such a row is impossible;zero other minors do not establish consistency,and D must not be divided.

Step identifiers and dependenciesRule: System_DZERO_zero_row_contradiction_guard_BEFORE_rank_or_minors · Uses: G001, S006





S008 · calculationBefore

System rank1 ORIGINAL a times f augmented minor := mul(1, 16)

After

System rank1 ORIGINAL a times f augmented minor = 16

Conditions: none

Use ORIGINAL operands/order for exact integer/rational arithmetic.RAW bounds are bank-specific;derived values are not SAFE-recapped or approximated.Do not import legacy caps into BASE integers.

Step identifiers and dependenciesRule: exact_rational_arithmetic · Uses: G001, S007





S009 · calculationBefore

System rank1 ORIGINAL c times d augmented minor := mul(8, 2)

After

System rank1 ORIGINAL c times d augmented minor = 16

Conditions: none

Use ORIGINAL operands/order for exact integer/rational arithmetic.RAW bounds are bank-specific;derived values are not SAFE-recapped or approximated.Do not import legacy caps into BASE integers.

Step identifiers and dependenciesRule: exact_rational_arithmetic · Uses: G001, S008





S010 · calculationBefore

System rank1 ORIGINAL augmented x minor := sub(16, 16)

After

System rank1 ORIGINAL augmented x minor = 0

Conditions: none

Use ORIGINAL operands/order for exact integer/rational arithmetic.RAW bounds are bank-specific;derived values are not SAFE-recapped or approximated.Do not import legacy caps into BASE integers.

Step identifiers and dependenciesRule: exact_rational_arithmetic · Uses: G001, S009





S011 · calculationBefore

System rank1 ORIGINAL b times f augmented minor := mul(6, 16)

After

System rank1 ORIGINAL b times f augmented minor = 96

Conditions: none

Use ORIGINAL operands/order for exact integer/rational arithmetic.RAW bounds are bank-specific;derived values are not SAFE-recapped or approximated.Do not import legacy caps into BASE integers.

Step identifiers and dependenciesRule: exact_rational_arithmetic · Uses: G001, S010





S012 · calculationBefore

System rank1 ORIGINAL c times e augmented minor := mul(8, 12)

After

System rank1 ORIGINAL c times e augmented minor = 96

Conditions: none

Use ORIGINAL operands/order for exact integer/rational arithmetic.RAW bounds are bank-specific;derived values are not SAFE-recapped or approximated.Do not import legacy caps into BASE integers.

Step identifiers and dependenciesRule: exact_rational_arithmetic · Uses: G001, S011





S013 · calculationBefore

System rank1 ORIGINAL augmented y minor := sub(96, 96)

After

System rank1 ORIGINAL augmented y minor = 0

Conditions: none

Use ORIGINAL operands/order for exact integer/rational arithmetic.RAW bounds are bank-specific;derived values are not SAFE-recapped or approximated.Do not import legacy caps into BASE integers.

Step identifiers and dependenciesRule: exact_rational_arithmetic · Uses: G001, S012





S014 · impliesBefore

source roles = [[[1, 6, 8], [2, 12, 16]]]

After

derived = [0, 0, Yes]

Conditions: none

AFTER excluding rank0/zero-row contradictions,the D0 coefficient rank is1.BOTH augmented minors must vanish for consistency;any nonzero minor yields an elimination contradiction.One zero minor is insufficient.

Step identifiers and dependenciesRule: System_RANKONE_BOTH_augmented_minors_consistency · Uses: G001, S013





S015 · calculationBefore

System free parameter ORIGINAL rhs over x pivot := div(8, 1)

After

System free parameter ORIGINAL rhs over x pivot = 8

Conditions: none

Use ORIGINAL operands/order for exact integer/rational arithmetic.RAW bounds are bank-specific;derived values are not SAFE-recapped or approximated.Do not import legacy caps into BASE integers.

Step identifiers and dependenciesRule: exact_rational_arithmetic · Uses: G001, S014





S016 · calculationBefore

System free parameter ORIGINAL negative y coefficient := sub(0, 6)

After

System free parameter ORIGINAL negative y coefficient = -6

Conditions: none

Use ORIGINAL operands/order for exact integer/rational arithmetic.RAW bounds are bank-specific;derived values are not SAFE-recapped or approximated.Do not import legacy caps into BASE integers.

Step identifiers and dependenciesRule: exact_rational_arithmetic · Uses: G001, S015





S017 · calculationBefore

System free parameter ORIGINAL x slope in free y := div(-6, 1)

After

System free parameter ORIGINAL x slope in free y = -6

Conditions: none

Use ORIGINAL operands/order for exact integer/rational arithmetic.RAW bounds are bank-specific;derived values are not SAFE-recapped or approximated.Do not import legacy caps into BASE integers.

Step identifiers and dependenciesRule: exact_rational_arithmetic · Uses: G001, S016





S018 · calculationBefore

System free parameter reverse OTHER x coefficient times constant := mul(2, 8)

After

System free parameter reverse OTHER x coefficient times constant = 16

Conditions: none

Use ORIGINAL operands/order for exact integer/rational arithmetic.RAW bounds are bank-specific;derived values are not SAFE-recapped or approximated.Do not import legacy caps into BASE integers.

Step identifiers and dependenciesRule: exact_rational_arithmetic · Uses: G001, S017





S019 · calculationBefore

System free parameter reverse OTHER x coefficient times slope := mul(2, -6)

After

System free parameter reverse OTHER x coefficient times slope = -12

Conditions: none

Use ORIGINAL operands/order for exact integer/rational arithmetic.RAW bounds are bank-specific;derived values are not SAFE-recapped or approximated.Do not import legacy caps into BASE integers.

Step identifiers and dependenciesRule: exact_rational_arithmetic · Uses: G001, S018





S020 · calculationBefore

System free parameter reverse OTHER add y coefficient := sum(-12, 12)

After

System free parameter reverse OTHER add y coefficient = 0

Conditions: none

Use ORIGINAL operands/order for exact integer/rational arithmetic.RAW bounds are bank-specific;derived values are not SAFE-recapped or approximated.Do not import legacy caps into BASE integers.

Step identifiers and dependenciesRule: exact_rational_arithmetic · Uses: G001, S019





S021 · impliesBefore

source roles = [[[1, 6, 8], [2, 12, 16]], 0]

After

derived = [[x = 8/1 + (-6/1)*t, y = t], 16/1, 0/1, t arbitrary in R]

Conditions: none

Choose an ACTUAL nonzero pivot and exhibit a free REAL parameter t.Substitution into the OTHER row gives its exact RHS and zero t-coefficient,so the WHOLE family solves.Different free-coordinate t values give infinitely many distinct solutions.

Step identifiers and dependenciesRule: System_RANKONE_explicit_free_REAL_parameter_and_ALL_row_identity · Uses: G001, S020









## Reverse checks


- S021 · premise_and_result_audit — Reverse-check ORIGINAL data,field roles,types,domain and premises;the conclusion need not uniquely recover its premises.Keep source-bound candidates,independent review,formal proof and publication separate.
- S020 · premise_and_result_audit — Recompute System free parameter reverse OTHER add y coefficient with exact rational arithmetic, not rounded decimals.
- S019 · premise_and_result_audit — Recompute System free parameter reverse OTHER x coefficient times slope with exact rational arithmetic, not rounded decimals.
- S018 · premise_and_result_audit — Recompute System free parameter reverse OTHER x coefficient times constant with exact rational arithmetic, not rounded decimals.
- S017 · premise_and_result_audit — Recompute System free parameter ORIGINAL x slope in free y with exact rational arithmetic, not rounded decimals.
- S016 · premise_and_result_audit — Recompute System free parameter ORIGINAL negative y coefficient with exact rational arithmetic, not rounded decimals.
- S015 · premise_and_result_audit — Recompute System free parameter ORIGINAL rhs over x pivot with exact rational arithmetic, not rounded decimals.
- S014 · premise_and_result_audit — Reverse-check ORIGINAL data,field roles,types,domain and premises;the conclusion need not uniquely recover its premises.Keep source-bound candidates,independent review,formal proof and publication separate.
- S013 · premise_and_result_audit — Recompute System rank1 ORIGINAL augmented y minor with exact rational arithmetic, not rounded decimals.
- S012 · premise_and_result_audit — Recompute System rank1 ORIGINAL c times e augmented minor with exact rational arithmetic, not rounded decimals.
- S011 · premise_and_result_audit — Recompute System rank1 ORIGINAL b times f augmented minor with exact rational arithmetic, not rounded decimals.
- S010 · premise_and_result_audit — Recompute System rank1 ORIGINAL augmented x minor with exact rational arithmetic, not rounded decimals.
- S009 · premise_and_result_audit — Recompute System rank1 ORIGINAL c times d augmented minor with exact rational arithmetic, not rounded decimals.
- S008 · premise_and_result_audit — Recompute System rank1 ORIGINAL a times f augmented minor with exact rational arithmetic, not rounded decimals.
- S007 · premise_and_result_audit — Reverse-check ORIGINAL data,field roles,types,domain and premises;the conclusion need not uniquely recover its premises.Keep source-bound candidates,independent review,formal proof and publication separate.
- S006 · premise_and_result_audit — Reverse-check ORIGINAL data,field roles,types,domain and premises;the conclusion need not uniquely recover its premises.Keep source-bound candidates,independent review,formal proof and publication separate.
- S005 · premise_and_result_audit — Recompute System ORIGINAL signed determinant ae minus bd with exact rational arithmetic, not rounded decimals.
- S004 · premise_and_result_audit — Recompute System ORIGINAL b times d other product with exact rational arithmetic, not rounded decimals.
- S003 · premise_and_result_audit — Recompute System ORIGINAL a times e main product with exact rational arithmetic, not rounded decimals.
- S002 · premise_and_result_audit — Reverse-check ORIGINAL data,field roles,types,domain and premises;the conclusion need not uniquely recover its premises.Keep source-bound candidates,independent review,formal proof and publication separate.
- S001 · premise_and_result_audit — Reverse-check ORIGINAL data,field roles,types,domain and premises;the conclusion need not uniquely recover its premises.Keep source-bound candidates,independent review,formal proof and publication separate.





## Result

infinitely many solutions

The full substitutions and premise checks give the original answer; source identity,format and status are unchanged.





## This question review and source binding

Review date: 2026-10-26

Original questions, answers, step expressions, numeric ASTs and historical records are retained. Source candidate labels remain historical and are not overwritten as formal proof.

Source hashes and review receipts
- input commit: 0f7be61e2c22317a4075561dc822c87d881a50db
- original question SHA-256: 8cb72a25f1c01e2e8139c22031ddb9ced74a842db5fd836b936eab48584931c6
- candidate record SHA-256: 921dea97a90bc7c89b1adffa5cc98eb70c4b1ed5a36abefb927e5840b11b69b2
- semantic review receipt SHA-256: 8b9ea3ddfab468e9e3f0a0fc0f7682987d5e030be0d7c8860fd85df19cbe183b
- question-first witness SHA-256: 066bfeab8fc279706861faade71b9a18a61a25235fc48700092f0488d2a6da6a
- Lean: NOT_RUN · human review: NOT_PERFORMED

[Same-source full JSON](https://ocme.evemisslab.com/data/question-derivations/questions/q-20261003-advance-20261004-r06-system-linear-equations-0038.json)




