When directed to completely factor the polynomial 4x2y5-8xy3, a student wrote 2xy3(2xy3-4). When the teacher did not give the student full credit, the student complained because when his answer is multiplied out, the result is the original polynomial. What went wrong?

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An automated water dispenser fills packets with one liter of water on average, with a standard deviation of 5 milliliter. the manual says that after a year of operation the dispenser should be tested to see if it needs recalibration. a year later a number of filled packets are set aside and measured separately. it is found that the average packet now contains about 0.995 liters. does the dispenser need calibration? explain your answer.

Write 5(6x+4)-2(5x-2) in the form a(bx+c) where a,b and c integers and a> 1