You can put this solution on YOUR website! i'm not sure what you mean by missing factor, but you can solve this equation as follows:
6x^4 = 3x^3
divide both sides of the equation by x^3 to get:
6x = 3 which gets:
x = .5
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substituting in the original equation, you get:
6*(.5)^4 = 3*(.5)^3
which becomes .375 = .375 proving the value of .5 for x is good.
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