Solve the simultaneous equations. (1) 2x + y = 18 (2)x − y = 6
In these simultaneous equations, there are two unknowns. The first is x, the second is y. The aim of a question like this is to find what x and y are equal too. A method to doing this is to rewrite one equations to make one of the unknowns the subject of the equations (This means that x or y will be after the equals sign alone, for example x-6=y). This would then be followed by substituting this into the other equations (the one you didnt use) to then give an equation with only one unknown.
Example Answer: taking (2) rearrange x-y=6 to equal x-6=y x-6 is the same as y, so rewrite equation 1 but write that instead of y 2x+y = 18 2x + x - 6 = 18 2x + x = 24 3x = 24 x= 8
SW
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