GAPSENSE EXERCISE BOOK ANALYSIS REPORT

The student demonstrates a functional understanding of the elimination method for simultaneous equations: they correctly identified that subtracting equation ② from ① eliminates the 2x term, obtained the correct value for b, substituted back into the correct equation, performed accurate arithmetic (4×2=8, 18−8=10, 10÷2=5), and arrived at the correct solution. The student also shows good metacognitive habits — labelling equations, noting that either equation can be used for substitution, and prompting a back-substitution check. The sole concern is a compressed/ambiguous notation in the elimination step ('3b = b ÷ 3' instead of '3b = 6 → b = 6 ÷ 3 = 2'), which omits the intermediate value 6. This is a presentation gap rather than a conceptual gap, but it is worth addressing because in harder problems (e.g. non-integer intermediates, or where the coefficient is not 1 after elimination) this shorthand could lead to undetected arithmetic errors. No evidence of gaps in integer operations, substitution, or linear equation solving. NOTE: No image was attached; analysis is based entirely on the Stage 1 transcription, which was assessed as clean. Confidence is slightly reduced for the notation interpretation because the exact visual layout of '3b = b ÷ 3' cannot be independently verified from an image.