Answer:
7x^3-7x^2+14x
Step-by-step explanation: hope I helped
Well, we can denote L and W for the length and width respectively. Lets say the A is the area, we have: 1. A=(L × W) as well as 2. 2(L+W)=400. We rearrange the second equation to get 3. W=200-L. From this, we can see that 0<L<200. Substitute the third equation into the first to get A=(200L-L²). put this formula into the scientific calculator and you will find a parabola with a maximum. That would be the maximum area of the enclosed area. Alternatively, we can say that L is between 0 and 200 when the area equals 0. (The graph you find will be area against length). As the maximum is generally found halfway, we substitute 100 into the equation and we end up with 10000.
Hope this helps.
Multply both sides of the equation by 7.

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When the variable is in the numerator of a proportion like this, you can solve it by multiplying by that denominator. That multiplication cancels the denominator and gives you the value of the variable.
In general, you multiply by the reciprocal of the coefficient of x. When that coefficient is 1/7, you multiply by 7/1. Of course, you know that 7/7 = 1 and that x/1 = x.