Solve algebraically the simultaneous equations: 6x=5-2y 12.5=3x+3y

  1. Rearrange both equations into the form ax + by = c. 3x+3y = 12.5 6x +2y = 5. 2) Make either x or y have the same coefficient in each equation. In this case we use x, to do this we multiply the first equation by two to get 6x. The second equation remains the same. 6x + 6y = 25. 6x + 2y =5. 3) We can now solve for y by subtracting equation 2 from equation 1. 4y = 20. y = 5. 4) Substitute y into the equation to find x. 6x + 10 = 5. x = -5/6. 5) Substitute your answers back into the equation to check they are correct. You may use a calculator.
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