12.5%, every 500 years you take away half of the substance (50%) -> 25% -> 12.5%
you divide your number 3 times because 1500/500=3
![\bf f(x)=(x-6)e^{-3x}\\\\ -----------------------------\\\\ \cfrac{dy}{dx}=1\cdot e^{-3x}+(x-6)-3e^{-3x}\implies \cfrac{dy}{dx}=e^{-3x}[1-3(x-6)] \\\\\\ \cfrac{dy}{dx}=e^{-3x}(19-3x)\implies \cfrac{dy}{dx}=\cfrac{19-3x}{e^{3x}}](https://tex.z-dn.net/?f=%5Cbf%20f%28x%29%3D%28x-6%29e%5E%7B-3x%7D%5C%5C%5C%5C%0A-----------------------------%5C%5C%5C%5C%0A%5Ccfrac%7Bdy%7D%7Bdx%7D%3D1%5Ccdot%20e%5E%7B-3x%7D%2B%28x-6%29-3e%5E%7B-3x%7D%5Cimplies%20%5Ccfrac%7Bdy%7D%7Bdx%7D%3De%5E%7B-3x%7D%5B1-3%28x-6%29%5D%0A%5C%5C%5C%5C%5C%5C%0A%5Ccfrac%7Bdy%7D%7Bdx%7D%3De%5E%7B-3x%7D%2819-3x%29%5Cimplies%20%5Ccfrac%7Bdy%7D%7Bdx%7D%3D%5Ccfrac%7B19-3x%7D%7Be%5E%7B3x%7D%7D)
set the derivative to 0, solve for "x" to get any critical points
keep in mind, setting the denominator to 0, also gives us critical points, however, in this case, the denominator will never be 0, so... no critical points from there
there's only 1 critical point anyway, and do a first-derivative test on it, check a number before it and after it, to see what sign the derivative has, and thus, whether the graph is going up or down, to check for any extrema
Answer:
- r = 3V/(2πh²)
- h = 3V/b²
- r = 25/π cm ≈ 7.9577 cm
- w = 15 cm
Step-by-step explanation:
1. Multiply both sides of the equation by the reciprocal of the coefficient of r.

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2. Multiply both sides of the equation by the reciprocal of the coefficient of h.

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3. Solve the circumference formula for r, then substitute the given information.

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4. Solve the perimeter formula for width, the substitute the given information and do the arithmetic.

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In general, solving for a particular variable involves "undoing" what has been done to the variable, usually in the reverse order. In part 4, the variable W has L added and the sum is multiplied by 2. We "undo" those operations, last operation first, by dividing by 2 and subtracting L.
The properties of equality say you can do what you like to an equation as long as you do the same thing to both sides of the equation. So, when we say "divide by 2", we mean "divide both sides of the equation by 2." Likewise, "subtract L" means "subtract L from both sides of the equation."
Answer:
0.15 for each message
Step-by-step explanation:
The charge per message can be found by dividing the charge by the number of messages. Using the first line of the table, we get ...
charge per message = (total charge)/(number of messages) = $38.40/256
charge per message = $0.15
Alyssa is charged 0.15 for each text message.
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We can check other lines of the table to see if charges are really proportional:
$26.55/177 = $0.15
$31.35/209 = $0.15
Answer:
Step-by-step explanation:
Given
There are 28 students in a class out of which
13 are boys so the remaining 15 are girls
Ratio of girls to boys in the class