A dish tv satellite dish is the shape of a paraboloid. the dish is 36 inches wide, and 8 inches deep. how many inches should the
receiver be located from the vertex for optimal reception? (round to the nearest thousandth)
1 answer:
Refer to the diagram shown below. It shows a vertical cross-section of the paraboloid through its axis of symmetry.
Let the vertex of the parabola be at the origin. Then its equation is of the form
y = bx²
Because the parabola passes through (18,8), therefore
8 = b(18²)
b = 0.02469
The parabola is y = 0.02469x².
The receiver should be placed at the focal point of the paraboloid for optimal reception.
The y-coordinate of the focus is
a = 1/(4b) = 1/0.098765 = 10.125 in
Answer: The receiver is located at 10.125 inches from the vertex.
Let the vertex of the parabola be at the origin. Then its equation is of the form
y = bx²
Because the parabola passes through (18,8), therefore
8 = b(18²)
b = 0.02469
The parabola is y = 0.02469x².
The receiver should be placed at the focal point of the paraboloid for optimal reception.
The y-coordinate of the focus is
a = 1/(4b) = 1/0.098765 = 10.125 in
Answer: The receiver is located at 10.125 inches from the vertex.
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Answer:
Joint variation states that:
If z is directly proportional to x and inversely proportional to y,
i.e, ,
then the equation is in the form: where k is the constant of variation.
From the given information: The volume V of a gas varies inversely as the pressure P and directly as the temperature
i.,e ,
by definition of joint variation:
.....[1] where k is the constant of variation.
It is also given that a certain gas has a volume of 10 liters(L) , a temperature of 300 kelvins(K), and a pressure of 1.5 atmosphere(atm).
Substitute these given values in [1] to solve for k;
Simplify:
Divide by 200 both sides we have;
Now, if a gas has a temperature of 400 kelvins and a pressure of 5 atm.
To find the volume (V);
Now substitute the given data and value of k in [1] we have;
Therefore, the Volume of a gas is, 4 liters
We have that
<span>y=-1/3(x+2)</span>²<span>+5
using a graph tool
see the attached figure
we know that
1) the graph open downward
2) the vertex of the graphic is the point (-2,5)
3) the axis of symmetry of the graph is x=-2
4) the x intercept values are (-5.873,0) and (1.873,0)
5) the y intercept value is (0,3.667)
</span><span>
</span>
<span>y=-1/3(x+2)</span>²<span>+5
using a graph tool
see the attached figure
we know that
1) the graph open downward
2) the vertex of the graphic is the point (-2,5)
3) the axis of symmetry of the graph is x=-2
4) the x intercept values are (-5.873,0) and (1.873,0)
5) the y intercept value is (0,3.667)
</span><span>
</span>
Answer:
Step-by-step explanation:
Let X be the length of pregnancy.
X is N(268, 15)
a) Prob of pregnancy lasting 307 days or longer
= P(X>307) =
=0.5-0.4953
=0.0047
b) Lowest 2% is 2nd percentile
Z=-2.55
X score = 268-2.55(15)
= 229.75 days
If length of days >230 days then it is not premature.