Medium
Solve the pair of linear equations for x: 1x + 3y = 15 and 5x + -3y = -15.
Explanation
Explanation
Using the elimination method: multiply the first equation by -3 and the second by 3, then subtract to eliminate y. Solving gives x = 0 (and correspondingly y = 5). You can verify: 1(0) + 3(5) = 15 ✓ and 5(0) + -3(5) = -15 ✓.
PRO TIP
Re-check your working by substituting the answer back into the original question.