<u>Formula</u>
<em>An expression that uses variables to state a rule is a </em><u><em>formula</em></u>
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Explanation:</h2>
An expression that uses variables to state a rule is a formula. It's important to know that formulas uses the equals sign (=) and includes two or more variables. Formulas gives us information that we express symbolically. For example, the well known formula for the volume of a sphere is defined as:

So in this formula we have a relationship between the volume of a sphere and its radius, so if we have information about the radius of it we can easily calculate the volume of it.
<h2>Learn more:</h2>
Volume of prism: brainly.com/question/12501166
#LearnWithBrainly
The answer is the 2nd choice, number of sales.
The function described f(x) = B + Cx
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.
20 5/81 in its simplest form is 20 5/81.
20 5/81 originally looks like this ⇒ 1625/81
((20 * 81)+5)/81 = (1620+5)/81 = 1625/81 * this is an improper fraction because the numerator is greater than the denominator. Improper fractions must be converted to proper fractions. It will then become a mixed fraction.
<u> 0020 5/81</u>
81 | 1625
<u>162 </u> * 81 x 2
05
Answer:
C = 106.76 cm
Step-by-step explanation:
In the diagram, we are given the diameter (d), which is 34 cm. Using the formula you are given, we know circumference is 3.14 × d
C = 3.14 × d
C = 3.14 × (34)
C = 106.76 cm
The circumference is around 106.76 cm