Solve the following system of equations simultaneously to find the values of x, y and z. 2x+3y+4z=3, -x-y+z=1, 2x+y-z=0

First scale one of the equations so that upon addition or subtraction from another of the equations we cancel one of the 3 variables, next do this again replacing one of the equations used with the unused equation so that we now have 2 equations in terms of just 2 of the 3 variables. Now, solve these equations by removing a variable in the same manner as before to get a value for one of the 3 variables. Substitute this value back into one of the formed equations to get another variable's value. Finally, substitute both known values into one of the original equations and solve to find the final variable's value. Answers: x=1 y=-1 z=1

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