Answer:
Step-by-step explanation:
V = 1/3 * pi * r^2 * h
r = ?
pi = 3.14
h = 17 cm
3*V = pi * r^2 h = r^2 Divide by pi
3*V/pi = r^2 h = r^2 Divide by h
3*V/(pi*h) =r^2 Take the square root of the left to get just r
sqrt(3*V/(pi*h)) = r Now solve the equation.
sqrt(3*538.25 /(3.14*17)) = r
sqrt(1614 / 53.38) =
r = sqrt(30.24)
r = 5.493
Fourty and eight tenths as a decimals is 40.8. More than one pounds behind decimal is too much and a different number other than 8 is wrong. The answer is B: 40.8.
(7 3/4 mi/h)*(2 2/3 h) = 20 2/3
Todd rode 20.667 miles.
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A calculator that works with mixed numbers is a handy thing.
This expression is called the Discriminant, also shown as Δ.
It is equal to b² - 4ac. This is a very important part of the quadratic formula as it determines whether x will have two values, one repeated value or no real values. Here are a few examples.
a) x² - 2x - 1. a is equal to 1 since 1x² = x². b = -2, c = -1
The discriminant will be (-2)² - 4×1×-1 = 4 + 4 = 8.
Since Δ > 0, there are two x values. Graphed, the parabola sinks below the x axis.
b) x². a = 1, b = 0 (0x = 0), c = 0
The discriminant will be 0² - 4×1×0 = 0 - 0 = 0.
Since Δ = 0, there is only one x value. Graphed, the parabola touches the x axis at only one point.
c) x² + 1. a = 1, c = 1.
The discriminant will be 0² - 4×1×1 = 0 - 4 = -4
Since Δ < 0, there are no real x values. Graphed, the parabola floats above the x axis.
Hope this helps!
