3x +1
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x-4 l 3x² -11x -4
3x²-12x
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x -4
x -4
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0
First, do 3x² ÷x, the quotient is 3x, put it above the -11x, 3x(x-4)=3x²-12x, put it under the divisor, make sure you line them up according the the exponents. 2nd power under 2nd power, 1st power under 1 power, constant under constant. subtract to get the remainder x. move down the constant -4, now you have x-4. x-4 divided by (x-4)=+1, put the quotient +1 above the constant -4. the remainder is 0.
I hope I've made myself clear.
so the answer is 3x+1