Chapter: Linear Equations in Two Variables· Mathematics Part 1 (Algebra)
Answer: \(x - y = -5\)
Subtract the second equation from the first:
\((17x + 15y) - (15x + 17y) = 11 - 21\)
\(\therefore 2x - 2y = -10\)
\(\therefore x - y = -5\)
(Adding instead gives \(32x + 32y = 32\), so \(x + y = 1\), which is what June 2026 asked.)