Hard
Solve the pair of linear equations for x: 4x + 1y = 27 and 5x + -4y = 18.
Explanation
Explanation
Using the elimination method: multiply the first equation by -4 and the second by 1, then subtract to eliminate y. Solving gives x = 6 (and correspondingly y = 3). You can verify: 4(6) + 1(3) = 27 ✓ and 5(6) + -4(3) = 18 ✓.
PRO TIP
Re-check your working by substituting the answer back into the original question.