The dimensions of the bottom of a rectangular swimming pool are shown on the diagram at the right. The area of the bottom of the pool is 45 square yards. What is the length of the pool, in yards?

Question

The dimensions of the bottom of a rectangular swimming pool are shown on the diagram at the right.  The area of the bottom of the pool is 45 square yards. What is the length of the pool, in yards?

anonymous · Answer

|dw:1365967113803:dw|

anonymous · Answer

this one is easy

anonymous · Answer

Really, then it should be easy for you to help me.

anonymous · Answer

yes it is

anonymous · Answer

Are you going to help me?

anonymous · Answer

yea sure

anonymous · Answer

ok then

anonymous · Answer

Shall we start? We as in you telling me how to start this

anonymous · Answer

calm down. ok lets start

anonymous · Answer

well first of all, you have to find out what 2x-1 equals.

anonymous · Answer

and the bottom of the pool is 45 sq. yards, so 2 x 46-1=45 and 45 is the square yards of the pool

anonymous · Answer

then you divide 46 by 2 which gives you 23 yards.

anonymous · Answer

23 yards or square yards is your answer. which ever one you need but 23 is the number of the answer. ok you are finished

anonymous · Answer

Thanks. That wasn't that hard to explain to me now was it?

anonymous · Answer

no it was not :D

espex · Answer

Are you certain the length of the pool isn't 9?

anonymous · Answer

nope

anonymous · Answer

why would it be 9?

espex · Answer

Well, your area is 45, calculated by multiplying width x length. So you have (x)*(2x-1)=45, distribute your x and you get $$2x^{2}-x=45$$ set the equation equal to zero by moving the 45 to the other side. $$2x^{2}-x-45=0$$ and solve for x. Using the quadratic equation you get an answer of -9/5 or 5, since x cannot be negative then it must be 5. So (2)*(5)-1=9

espex · Answer

So if your length is 9, your width, x, is 5, 9*5=45

anonymous · Answer

so it's 9 then?

espex · Answer

I believe it is, you decide which answer makes sense to you and choose that one. :)

anonymous · Answer

OK

anonymous · Answer

I choose 9

anonymous · Answer

but where was the number 46 because you need 46 because you multiply 23 x 2 and it is 46 and then you had to subtract 46 by 1 which gave you 45. i did that backwards because it made more sense. so the product would be 23 but choose 9 idrc

espex · Answer

@goldberg You got 46 because you were looking at the length alone, 2x-1, however the problem statement said the area was 45 and that is l*w

anonymous · Answer

oh yes i didnt even see tht. thnk you so much for showing me. i appreciate it @eSpeX