SOLUTION: Here is the problem. I tried several ways but I'm probably way off. Swimming pool. The length of a rectangular swimming pool is 2x - 1 meters, and the width is x + 2 meters. W

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Question 7689: Here is the problem. I tried several ways but I'm probably way off.

Swimming pool. The length of a rectangular swimming pool is 2x - 1 meters, and the width is x + 2 meters. Write a polynomial that represents the area. Find the area if x is 5 meters.

So, this is what I did.

(2x - 1)(x + 2)
(10-1) (5 + 2)
9 * 7 = 63
Area = 63 meters

OR......

(2x - 1)^2(x + 2)^2
(10-1)^2 (5 + 2)^2
9^2 * 7^2
81 * 49
Area = 3969 meters (I think this one is wrong)

OR..... using FOIL

(2x -1) (x + 2)
2x^2 + 4x - x - 2
2x^2 + 3 - 2
2x^2 + 1
2(5)^2 +1
Area = 51 meters

OR....
Multiplying vertically
2x - 1
x + 2
4x - 2
2x^2 +x
2x^2 + 5x - 2
50 + 25 - 2
Area = 73 meters

I tried, please tell me if I'm close. Thanks so much in advance for your help. I really appreciate it.

Found 2 solutions by Earlsdon, prince_abubu:
Answer by Earlsdon(6294) (Show Source):
You can put this solution on YOUR website!
It seems like you went overboard (no pun intended) on your solutions to the swimming pool problem.
Your first try is your best and is actually correct, to some extent.

Since L = 2x-1 and W = x+2, then the area is:

This the polynomial that represents the area.
If x = 5, then:

Note that the area is 63 square meters, not meters.

Answer by prince_abubu(198) (Show Source):
You can put this solution on YOUR website!
Your first attempt is correct.

You tried to square the sides first on your second attempt. You know that area is L*W = A instead of .

On the FOIL, the third line that read should have been because 4x - x from the line above equals 3x. If you plugged in 5, you'd get .

On the multiplying vertically, you had x multiplied by 2x - 1. That should give you instead of the + x. The +x caused your x-term to be 5x instead of the 3x it was supposed to.