How to solve a simple simultaneous equation

Solving simultaneous equations: Example Question:Equation 1 --->         2y – 4x = 2Equation 2 --->         4y – 6x = 10 Find the unknown quantities, x and y. Solution:Step 1: Firstly check whether there are more than 2 unknowns in the given question.If there are more unknowns than given equations – the problem cannot be solved. Step 2: Eliminate one unknown quantity by rearranging one of the equations such that x terms are on one side and the y terms are on the other sideRearraging Equation 1:         y = 1 +2x    ---> (Equation 3) Step 3: Substitute y (equation 3) into equation 2 - such that only one unknown quantity exists within the equation:4y – 6x = 104 ( 1 + 2x) – 6x = 10Expanding the above ---> 4 + 8x – 6x = 10 Step 4: Bring x terms onto one side and numbers onto the other side:8x - 6x = 10 - 42x = 6;therefore x = 6/2=3x=3 Step 5: Substitute x =3 into equation 1 or 2 to find the value of yIn this case, Equation 1 is chosen2y – 4x = 22y – 4(3) = 22y – 12 = 22y=14y= 7 Final Answer: x=3; y=7      

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