Question 71907: the old lion cage at the zoo was a square, with sides x meters long. For part of the zoo's 50th b-day celebration, the zoo expanded the length and width of the cage. The expression for total area of the new cage is (x^2 + 18x + 81). square meters.
a.robert thinks the length was incresed by 6 meters and the width was increased by 8 meters. is he right? explain why or why not.
b.How much did the zoo expand the length and width of the cage?
Answer by jim_thompson5910(35256)   (Show Source):
You can put this solution on YOUR website! If you factor x^2 + 18x + 81 you will have a product of factors. These factors represent the sides, which if multiplied become the area of x^2 + 18x + 81. So we need to find 2 numbers which add to 18 and multiply to 81; these 2 numbers are 9 and 9.
So x^2 + 18x + 81 factors to (x+9)(x+9). (x+9) is the length of the new sides, where x is the original length. The lengths of all of the sides were increased by 9, not 6 and 8, so this shows he was wrong.
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