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Powers |
2010-10-20 |
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From dylan:
how do you write 20736 in exponential form .same for 1728 and 50625.
is there a formula to figure out how to express large know numbers in exponential form.
Answered by Penny Nom. |
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The equation of a circle |
2010-10-20 |
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From Silvan:
Hi, I just want to find the x,y values for the circumference of a circle...
Lets take a clock having its centre at (0,0) in a graph.
I just want to know how to find the (x,y) co-ordinates for the curved path or the surface of the circle..
Is there any formula to directly align the curved path or the circumference of the circle in a graph for a known radius of a circle..
I feel it will be useful for me to draw a clock in a graph... :-)
Answered by Penny Nom. |
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An exponential equation |
2010-10-19 |
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From Sandi:
Question from sandi, a student:
I have several questions similar to this one and was wondering if you could walk me through this one. I'm totally lost on how to do it.
Paramecia reproduce by splitting in two. In a laboratory flask, a colony of paramecia had an initial population of 500. Each day, the population of the paramecia was counted. The results are as listed.
Time (in days)------Population
0-----------------------500
1-----------------------600
2-----------------------720
3-----------------------864
4----------------------1037
5---------------------1244
6---------------------1493
7----------------------1792
8---------------------2150
1.)Using graphing calculator make a scatter plot of the data in table.
I think I did this part right I set my window at Xmin=0 Xmax=10 Xscl=1 Ymin=0 Ymax=2500 Yscl=100 Xres=1
2.) Determine an exponential equation to represent the population as a function of time without using a graphing calculator.I have no clue how to do this.
3.)Suppose the flask and food supply is large enough to support the trend of the population growth. Estimate the population of the colony when the time is 10 days.
Answered by Penny Nom. |
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A commuter airline between two cities |
2010-10-19 |
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From Adori:
An airline runs a commuter between two cities that are 720 miles apart. If the average speed of the planes is increased by 40 miles per hour, the travel time is decreased An airline runs a commuter between two cities that are 720 miles apart. If the average speed of the planes is increased by 40 miles per hour, the travel time is decreased by 12 minutes. What airspeed is required to obtain this decrease in travel time?
Answered by Penny Nom. |
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The equation of a line |
2010-10-19 |
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From Sava:
I have to write an equation and sketch a graph for the line that meets the given conditions:
A line with slope -15/5 that passes through the point (-2.5,4.5)
Answered by Penny Nom. |
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A scale factor |
2010-10-17 |
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From david:
We have to rectangles with measurements and we need to find the scale factor. The rectangles are W=6 L=4 for first and second is W=4 and L=3.
thanks for your help
Answered by Penny Nom. |
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An algebra problem with fractions |
2010-10-16 |
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From Morgan:
Hi my math teacher has given us this question for our grade nine math
class and I always get confused about multiple x algebra, could you help me?
6x+4 3x+2
------ = ------
3 5
I have no problems until it comes to combining integers, or x's
Answered by Penny Nom. |
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The angles in an m-gon and genrealizations |
2010-10-16 |
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From Michael:
Hello:
In answer to a student's question, someone named Penny from
your organization provided a proof that the sum of the interior
angles of a triangle in the plane is pi radians (or 180 degrees).
I am interested (and I'm sure many other people would be too) in
3 potential generalizations of this basic fact in plane geometry:
Answered by Walter Whiteley. |
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Geocaching |
2010-10-15 |
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From Clint:
I am stuck on a puzzle for Geocaching which is a GPS game.
I know it is a number matrix but don't know how to start.
[1 -7 16 -3 -9; 1 -3 18 -20 -33] x [1 8 -9 3 5; 0 1 0 4 2; 0 0 1 2 1; 0 0 0 1 -1; 0 0 0 0 1] = ?
Answered by Stephen La Rocque. |
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A linear system |
2010-10-15 |
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From Sandy:
HARD!! algebra (Linear Systems) question?
An Airplane cruises at 120km/h in still air. One day, when the wind was blowing steady from the west, the airplane travelled west (flying into the wind) and landed at its desination after 1.5h. The airplane's return trip (flying with the wind) was only 1.0 h long. On both legs, the airplane travelled at its cruising speed. (meausred with respect to the air surrounding the airplane).
Part A
Write a System of equations that would allow you to determine the speed of the wind blowing that day and the distance travelled each way
Part B
When solving the system of equations graphically, what equations would you enter into the equation editior (to make graphs on your calculator)
Part C
Indicate what the X and the Y represent
Answered by Stephen La Rocque. |
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Two jets leave denver at 9 am. |
2010-10-15 |
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From Carl:
two jets leave denver at 9 am. One flying east at a speed of 50 km per hour greater than the other which is traveling west. At 11 am the planes are 2500 km apart. Find their speeds.
Answered by Stephen La Rocque. |
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Mathematics and medicine |
2010-10-13 |
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From Dixie:
need equations used in medicine for medicine and intravenous administration
Answered by Penny Nom. |
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Simplifying fractions |
2010-10-13 |
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From Alice:
14times (9divied3) + 12
______________________
18 divied (26-24)
don't get this.......
Answered by Penny Nom. |
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The volume of a truncated pyramid |
2010-10-12 |
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From A:
what is the formula to find out volume of a pyramid with individual length and breadth? For example bottom size is 6.5m x 6.5m, top size 1.5m x 4.2m and height 0.8m. please send me the formula.
Answered by Stephen La Rocque. |
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30,000 US gallons of water |
2010-10-12 |
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From mike:
If a swimming pool can hold 30,000 US gallons of water - is it possible to calculate the number of yards of dirt it would take to fill the hole?
Answered by Penny Nom. |
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