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Finding a parabola's equation by looking at its graph |
2007-04-30 |
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From Kenzie:
The graph shows an arrow going upward crossing at the -2 on the x line
and crossing the 3 on the x line and the vertex on the -6 on the y line.
Answered by Stephen La Rocque. |
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A couch sliding off a truck |
2007-04-30 |
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From William:
A couch with a mass of 1 X 10^2kg is placed on an adjustable ramp connected to a truck. As one end of the ramp is raised, the couch begins to move downward. If the couch slides down the ramp with an acceleration of .70 meters per second when the ramp angle is 25 degrees, what is the coefficient of kinetic friction between the ramp and couch?
I drew a force diagram and if I did it correctly I identified the forces involved as "mg" (mass x gravity), "Fn" (normal force) and the "Ff" (frictional force). I know that we have the couch sliding down the ramp a .70 m/s but I don't think this a force and I'm not sure how this info fits into the problem. I know that the formula for calculating the coefficient of friction is Ff/Fn. Based upon the force diagram I drew and calculated Fn to be 1082N. I can't seem to get past this point. How do I determine what the frictional force is?
Answered by Stephen La Rocque. |
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What is the origin of pi? |
2007-04-30 |
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From Aastha:
from where has been tha value of "pi" derived? or what is the origin of "pi"
Answered by Penny Nom. |
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Course grades |
2007-04-30 |
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From vince:
Question from vince, a student:
If you have 5 tests and the grades are 78,80,88,60,75 what is your Earn Point
for the tests
earn points= average times percent
Answered by Penny Nom. |
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Le pourcentage en +ou en- que représent la diférence de 2 nombres |
2007-04-29 |
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From Jean:
pouvez vous me donner la formule pour trouver
le pourcentage en +ou en-
que représent la diférence de 2 nombres ex: 8594 et 7634
Answered by Claude Tardif. |
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I have N data points in m-dimensional space |
2007-04-29 |
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From Sid:
Hi,
Given below is the problem that I am facing:
I have N data points in m-dimensional space. I know the mean euclidean distance of the points from one given point (say the origin). Now I wish to find the mean Euclidean distance of the N points from another given point. How can i do this without knowing the values of the N points and only knowing the 2 origin points and the mean distance from one of the origin points ?
Answered by Penny Nom. |
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LCD |
2007-04-29 |
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From Jackson:
I am having trouble getting the LCD for the following question.
1 3/8 x 8/9=
Answered by Penny Nom and Melanie Tyrer. |
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Simplifying a rational expression |
2007-04-29 |
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From Tamika:
X^2 + 10X + 24
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X + 6
SIMPLIFY EACH RATIONAL EXPRESSION (IF YOU CAN'T SIMPLIFY IT, WRITE ALREADY SIMPLIFIED)
Answered by Stephen La Rocque. |
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Two equations |
2007-04-29 |
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From lavon:
I'm having trouble figuring out a linear equation, can you help?
- 3x + 2y = 8
3x + 2y = 8
Answered by Penny Nom. |
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Maximum area |
2007-04-29 |
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From fee:
Given a perimeter of 24cm, calculate the maximum area using quadratics.
Answered by Penny Nom. |
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Finding out if two line equations are parallel or perpendicular |
2007-04-28 |
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From Vincent:
Can you determine if the two lines are parallel, perpendicular, or neither
1/2x+4y=3/5
y/1 + 10/5= 8x
I think there perpendicular but how would you solve the equations
Answered by Stephen La Rocque. |
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Incremental standard deviation |
2007-04-28 |
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From Murtaza:
Hi
In relation my question asked earlier, i would first like to thank you for the prompt reply. But it has not answered my query yet. Let me frame the problem again.
I have a mean value for N data items. (note that i know N but i donot know the distinct N data item values) Now the (N+1)th data item comes in and i calculate the new mean. (incremental method for that is simple). How do i calculate the new standard deviation. The formula you gave me requires me to read the data items once and at the end of the pass i will have have the standard deviation. But i need the STDDEV values at intermediate stages as well. Is it possible ?
Murtaza
Answered by Penny Nom. |
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The area of a pyramid |
2007-04-28 |
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From Alexander:
Total area of the plate required to fabricate a vessel(pyramid) the base is 0.6mx0.6m and height of 1.0m.
Answered by Stephen La Rocque. |
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The grade of a shoulder |
2007-04-28 |
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From Robert:
I am building a road with a 1.2 meter shoulder. The plan calls fo a 6% shoulder grade. When I use my metric calculator I come up with a different answer when I multiply 3/4 of an inch by 1.2 meters and when I multiply 1.2 meters by .06%?
Answered by Penny Nom. |
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A line parallel to a given line |
2007-04-28 |
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From vince:
write an equation of the line satisfying the given conditions
Through (2,-3) parallel to 2x=3y+5 and graph both equations
Answered by Penny Nom. |
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