Answer:
Final answer is approx x=-0.66.
Step-by-step explanation:
Given equation is 
.
Now we need to solve equation and round to the nearest hundredth.
Now use calculator to calculate log values, we get:
Round to the nearest hundredth.
Hence final answer is approx x=-0.66.
"y varies directly as x" means y = kx
you do not know what k is yet, other than that it is some constant number.
Now plug in the given values, y=12 when x=4, in the equation
12 = 4k
=> k = 3
Now rewrite the equation with the k value you just found
y = 3k
Substitute 18 in place of x
y = 3(18)
y = 54
You will have to set up a system of equations
9514 1404 393
Answer:
8000π mm^3/s ≈ 25,133 mm^3/s
Step-by-step explanation:
The rate of change of volume is found by differentiating the volume formula with respect to time.
V = 4/3πr^3
V' = 4πr^2·r'
For the given numbers, this is ...
V' = 4π(20 mm)^2·(5 mm/s) = 8000π mm^3/s ≈ 25,133 mm^3/s
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<em>Additional comment</em>
By comparing the derivative to the area formula for a sphere, you see that the rate of change of volume is the product of the area and the rate of change of radius. This sort of relationship will be seen for a number of different shapes.
It's C.
multiply by 3
x = 4, y = 4x3 = 12
x = 5, y = 5x3 =15
x = 6, y = 6x3 =18
