You can put this solution on YOUR website! 4000=4*1000=4*25*40=4*25*4*10. Since we can't break it into more perfect squares, we take the square root of the perfect squares and leave the imperfections under the square root sign.
so sqrt(4000) = sqrt(4*25*4*10) = sqrt(4)*sqrt(25)*sqrt(4)*sqrt(10) = 2*5*2*sqrt(10) = 20*sqrt(10)
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