Simultaneous linear equations
Equations and inequalities · Mathematics
Study notes
Q: Solve 3x + 2y = 12 and x - y = 1. Step 1 (substitution): From the second equation, x = y + 1. Step 2: Substitute into the first: 3(y + 1) + 2y = 12. Step 3: Expand: 3y + 3 + 2y = 12, so 5y = 9, y = 9/5. Step 4: x = 9/5 + 1 = 14/5. Step 5: Check: 3(14/5) + 2(9/5) = 42/5 + 18/5 = 60/5 = 12. Correct!