5x^2-9x+4=0 zero product property

Under normal conditions, 1.5 feet of snow will melt into 2 inches of water. during a winter season high in the mountains, 301 feet of snow fell. how many inches of water will there be when the snow melts?

George has seven boxes of five pencils. giulio three boxes of eight pencils. one of the boys arranges all his pencils equally into two groups. was this george or giulio how many are in each group explain

[10 points, algebra 2]according to my answer key the restrictions are -1 and 4. but why not positive 1?