Hey Pf, I'm working on precalculus review and I have found myself stumped by a question.(adsbygoogle = window.adsbygoogle || []).push({});

1. The problem statement, all variables and given/known data

A rectangular field is enclosed by 600m of fencing. A second rectangular field, which is alongside a river, has the same area and is also enclosed by 600m of fencing. However, this second field has fencing on only three sides because there is no need for fencing along the riverbank. Create a system of quadratic equations to model the problem. (Answer: A = -x^{2}+300x, A = -2x^{2}+60x)

2. Relevant equations

ax^{2}+bx+c

3. The attempt at a solution

I began by modeling the first field:

P = 2x+2y

600 = 2x+2y

300 = x+y

y = -x+300

A = xy

A = x(-x+300)

A = -x^{2}+300x

Afterwards I modeled the second field:

600 = 2x+y

y = -2x+600

A = xy

A = x(-2x+600)

A = -2x^{2}+600x

As you can see, the equations are different. I cannot see where I went wrong. Could someone please correct my folly? :)

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# Homework Help: Question Regarding System of Equations

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