Solve the simulaneous Equations: 5x + y = 21, x - 3y = 9
Steps to solve a simultaneous Equation:1) Make x and y coefficients the same2) Subtract or add (of which depends on scenario) equations to eliminate x or y3) Solve remaining variable4) Plug into other equation to find x or y(1) 5x+y=21(2) x-3y=9 ---------- (Multiply (2) by 5)5x + y = 215x - 15y = 45----------- (1)-(2)0 +16y = -24, y = -1.5----------- (Plug -1.5 into y in equation (1))5x - 1.5 = 215x = 22.5x = 4.5
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