The water level in a lake was 22 inches below normal at the beginning of March. The water level decreased by 3 1/6 inches in Mar
1 answer:
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Answer:
Part a) (see the explanation)
Part b) see the explanation
Part c) The graph in the attached figure
Step-by-step explanation:
<u><em>The complete question is</em></u>
With a family bowling pass, families can bowl for $4 per game. The pass costs $10 per year. Use an equation, a table, and a graph to explain the relationship between the total amount of money spent on bowling in a year, a, and the number of games a family plays in a year, g. Part A Use words and an equation to represent this problem. Part B Create a table to show values for g and a. Part C Use the values from your table to draw a graph.
Part A) Use words and an equation to represent this problem
Let
a ----> the total amount of money spent on bowling in a year
g ---> the number of games a family plays in a year
we know that
The linear equation in slope intercept form is equal to
where
m is the slope or unit rate
b is the a-intercept or initial value
In this problem we have
substitute
Part b) Create a table to show values for g and a
Assume different values of g and calculate the corresponding values of a
For g=0 ---->
For g=1 ---->
For g=2 ---->
For g=3 ---->
For g=4 ---->
The table is
Part c) Use the values from your table to draw a graph
we have the ordered pairs
Plot the ordered pairs and join them to graph the line
The graph in the attached figure
Answer:
Step-by-step explanation:
Any point on a given parabola is equidistant from focus and directrix.
Given:
Focus of the parabola is at .
Directrix of the parabola is .
Let be any point on the parabola. Then, from the definition of a parabola,
Distance of from focus = Distance of
from directrix.
Therefore,
Squaring both sides, we get
Hence, the equation of the parabola is .
Answer: About 72 feet
The more accurate value is roughly 71.7260397 feet (however, this value isn't fully exact either).
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Explanation:
Check out the diagram below. It's effectively the same diagram your teacher provided, but I've added points M and N. I've left out any unnecessary lines.
- M = center of the circle
- N = location where the cable is anchored to the ground
We're told that "(the length of cable from) E to the ground is 35 feet", so this is the red portion of cable that I've marked this as NE = 35, ie segment NE is 35 feet long. We're also told that NF = 40 feet, which is also shown in red.
The blue portions are chords of the circle. We're given one chord as LE = 80 ft, while the other chord JF is what we want to find out.
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What we need to find is the radius of this circle. Right away, it's not clear what the radius is; however, we can use the chord LE = 80 to help find it.
It turns out that the chord length c is connected to the radius r and central angle theta like so:
c = 2*r*sin(0.5*theta)
where theta must be in radian mode. The central angle subtends the arc that forms the chord in question.
If we started at point L, and counted the number of spaces to get to E while going clockwise, then we can see that there are 5 spaces
Those five spaces could be written as
- The jump from L to A
- The jump from A to B
- The jump from B to C
- The jump from C to D
- The jump from D to E
Or you could mark it as such on the diagram for a visual reference. Overall, the circle has been cut into 12 equal slices. So going from L to E, going clockwise, will have us take up 5/12 of the full circle.
There are 2pi radians in a full circle, meaning the central angle LME is (5/12)*2pi = 5pi/6 radians.
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Plug theta = 5pi/6 and c = 80 into the formula mentioned. Isolate the radius.
c = 2*r*sin(0.5*theta)
80 = 2*r*sin(0.5*5pi/6)
80 = 2*r*sin(5pi/12)
80 = 2*r*0.9659258
80 = 2*0.9659258*r
80 = 1.9318516r
1.9318516r = 80
r = 80/1.931 8516
r = 41.4110483
The radius is approximate. The radius is in feet. Make sure your calculator is in radian mode.
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Now that we know the radius, we can determine how long chord JF is.
The central angle for chord JF is angle JMF
If we start at J and go to F, along the shorter path, then we've gone 4 spaces. This is 4/12 = 1/3 of the full circle. So the radian measure of angle JMF is (1/3)*2pi = 2pi/3 radians.
So,
c = 2*r*sin(0.5*theta)
c = 2*41.4110483*sin(0.5*2pi/3)
c = 71.7260397
Chord JF is roughly 71.7260397 feet long.
When rounding to the nearest foot, that's about 72 feet.
