Answer: 128
Step-by-step explanation: 3 x -2 + 70 = 64 + -2 + 70 = 128
B: nine and one over two ft
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.
Answer:
∠Q = 75°
Step-by-step explanation:
Start by recognizing that the triangle is isosceles (the long sides are marked as being equal-length). That means angles Q and R have the same measure.
Next, you use the fact that the sum of angles is 180° to write an equation.
∠R +∠P +∠Q = 180°
(2x +15)° +x° +(2x +15)° = 180° . . . . substitute the known values
5x +30 = 180 . . . . . . . . . . . . . . . . divide by °, collect terms
5x = 150 . . . . . . . . subtract 30
x = 30 . . . . . . . divide by 5
Then angle Q is ...
∠Q = (2x +15)° = (2×30 +15)°
∠Q = 75°