How do I solve a simultaneous equation?

Simultaneous equations are a set of equations that have multiple common unknown variables such as two equations which both contain the unknowns x and y. To solve a simultaneous equation the trick is to change one of the equations so that it has the same amount of one of the unknowns as the other equation! The rule you should follow when changing the equation is that you can multiply one side of the equation by a certain amount as long as you do the same to the other side of the equation. So if you have 2x on one side and you want this to become 4x, you have to multiply both sides of the equation by 2!Once you have altered the first equation to match the second equation so they both have the same amount of x's. You then have to add or subtract one of the equations from the other so that the x's cancel out and you are left with only the other variable which you can then solve as a simple algebraic formula. We can practice with this exercise:2x +6y = 14, 2y + 4x = 8

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Answered by Lewis K. Maths tutor

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