Answer:
a) Y(x) = {900, x≤30; 900-40(x-30), x>30}
b) T(x) = {900x, x≤30; 2100x-40x², x>30}
c) dT/dx = {900, x≤30; 2100-80x, x>30}
Step-by-step explanation:
a) The problem statement gives the function for x ≤ 30, and gives an example of evaluating the function for x = 35. So, replacing 35 in the example with x gives the function definition for x > 30.

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b) The yield per acre is the product of the number of trees and the yield per tree:
T(x) = x·Y(x)

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c) The derivative is ...

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The attached graph shows the yield per acre (purple, overlaid by red for x<30), the total yield (black), and the derivative of the total yield (red). You will note the discontinuity in the derivative at x=30, where adding one more tree per acre suddenly makes the rate of change of yield be negative.
1.) 1+10a-5a
Subtract 5a from 10a
Final Answer: 1+5a
3.) x-9-3x
Subtract 3x from x
Final Answer: -9-2x
5.) 1-4n+2n-1
Subtract 1 from 1
-4n+2n
Add
Final Answer: -2n
7.) 10k-3k
Subtract
Final Answer: 7k
9.) 5r+4-4
Subtract
Final Answer: 5r
Answer:
C. $0 because $25.36 and -$25.36 are additive inverses.
Step-by-step explanation:
Additive inverses means 2 numbers that are the complete opposite.
When additive inverses are added together, their sum is 0.
Example: 1 and -1.
They're both additive inverses because they're on the opposite sides on the number line, if -1 had to be a positive, it wouldn't be an inverse.
<u>Given:</u>
- Before the deposit, her bank account balance is -25.36.
- She has deposited $25.36 into her bank account.
<u>Solve:</u>
Let's add both -25.36 and 25.36.
-25.36 + 25.36 = 0.
C. is the correct choice, and the reasoning is valid.
The better deal is the 21-ounce one because its unit rate equals less than the 17-ounce one
Answer:
The time spend to burn energy is 3300 minutes .
Step-by-step explanation:
Given as :
The speed at which the bike ride = 10 miles per hours
The energy burn while riding = 550 calories
Let The time spend to burn energy = t minutes
So, According to question
Time spend = 
i.e t =
hours
∴ t = 55 hours
So, in minutes
The time spend
1 hours = 60 min
∴ 55 hours = 60 × 55 = 3300 minutes
So, The spend to burn energy = t = 3300 minutes
Hence The time spend to burn energy is 3300 minutes . Answer