You can put this solution on YOUR website! Yes it is because the power of the variables ( x and y ) is one. If you had an equation which contained or then the equation would not be linear, because the power of the variables is higher than 1 and if you were to graph it, your graph would not look like a line. The best way to differentiate is the formula for linear equations, which is ie . If your equation looks like the above then you have a lindear equation.
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