I think this problem is 3
Answer:
625 metres
Step-by-step explanation:
Given the area function expressed as a(w)=-(w-25)^2+625.
The maximum area occurs at when da/dw = 0
da/dw = -2(w-25)
0 = -2(w-25)
-2(w-25) = 0
w - 25 = 0
w = 25
Substitute w = 25 into the modeled equation;
Recall a(w)=-(w-25)^2+625.
a(25)=-(25-25)^2+625
a(25) = 0+625
a(25) = 625
Hence the maximum area possible is 625 metres
<h3>
Answer: 2 < x < 7</h3>
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Explanation:
The 85 degree angle is smaller than the 90 degree angle (aka right angle). That must mean 5x-10 is smaller than 25
At the same time, 5x-10 must be larger than 0 to avoid having a 0 length or negative length.
So overall we can say 0 < 5x-10 < 25
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Let's isolate x
0 < 5x-10 < 25
0+10 < 5x-10+10 < 25+10 ...... adding 10 to all sides
10 < 5x < 35
10/5 < 5x/5 < 35/5 .... dividing all sides by 5
2 < x < 7
This says that x is between 2 and 7, but we cannot have x equal either endpoint.
