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Squares and triangles |
2011-12-06 |
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From Liaqath:
You have squares and triangles.
Altogether there are 33 sides.
How many squares do you have?
How many triangles do you have?
Answered by Penny Nom. |
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The arc of a bridge |
2011-12-05 |
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From Marioneta:
Two same columns placed symmetrically, 40 m apart.
The height of columns is 8 m.
If the origin of the coordinate system is placed at the foot
of the left column the equation of the arc of the bridge:
f (x) =-1/80x^2+1/2x+8
What is the maximum height of a boat sailing under the bridge and
identify its path.
Answered by Penny Nom. |
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A cube of ice is melting |
2011-12-05 |
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From Emily:
a cube of ice (i.e.) each side is of the same length) is melting at a rate such that the length of each side is decreasing at a rate of 5cm per hour. how fast is the volume of the cube decreasing (in cubic cm per hour) at the instant the length of each side is 25cm?
Answered by Penny Nom. |
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What is the altitude of the balloon? |
2011-12-04 |
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From C:
Chelcy and Jorgeare 2.32 miles apart. The observe a hot air balloon directly overhead between them Chelcy's angle of elevation is 28 degrees. Jorge's Angle of elevation is 37 degrees. What is the altitude of the balloon?
Answered by Penny Nom. |
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Two circles |
2011-12-04 |
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From Luke:
Two fixed circles intersect at A and B.
P is a variable point on one circle.
PA and PB when produced meet the other circle at M and N respectively.
Prove that MN is of constant length.
Thanks!
p.s. I also sent the question with a figure via email.
Answered by Chris Fisher. |
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Two parallel chords |
2011-12-04 |
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From violet:
Two parallel chords of a circle AB and CD on the same side of the centre measure 6 cm and 11 cm respectively. Find the radius.
Answered by Chris Fisher and Walter Whiteley. |
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Repeating a medication |
2011-12-02 |
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From ivan:
One person received the recommendation of a doctor taking the drug "Passaneura" every 10 hours. After a few days, noted that the time you should take the medication had not been repeated once. How many days since the first dose, will have to pass the time until recur
Answered by Penny Nom. |
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Solve for theta if 8cos^2 theta-3=1 |
2011-12-02 |
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From Katherine:
Hi,
I have just learned to solve trigonometric problems for theta and have one specific question in order to find the solutions to my homework.
I will use one example for this question. If I have 8cos^2 theta-3=1
I first divide by 8 and get cos^2theta=3/8
then I have cos theta= plus or minus the square root of 3/8
Then I assume that I plug in inverse cos (the square root of 3/8) to my calculator.
How do I find the four solutions (we are typically supposed to find four, I believe?)
Can you help me with finding the solution to this problem? Thank you!
Answered by Penny Nom. |
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The total number of roles that a user can be assigned |
2011-12-02 |
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From Colin:
Hi, I want to define an equation for calculating the total combination of roles that a user can be assign in a system.
Here is the background: There are two types of roles that a user can be assigned. These are object roles and data roles. There must be at least 1 object and 1 data role in the system. A user must be assigned at least 1 object role and at least 1 data role. A user can be assigned as many object roles and data roles as are created in the system. There is no upper limit to the number of roles that a user can be assigned except for the total number of object roles and data roles that exist. The number of object roles and data roles in the system are independent.
Can someone please assist? Thanks.
Answered by Penny Nom. |
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A suspension bridge |
2011-11-30 |
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From jennifer:
suspension bridges like the golden gate bridge, are used to span large distances.
when the main curved cables are attached to the deck by vertical cables they will end
up in the shape of parabola. assume that we need to build a bridge that spans
2,400 feet. the two towers 165feet tall each where placed at 400feet from either
side. the lowest point of the center of the bridge at 10feet. vertical suspension cables
where placed at 25foot interval. how many feet of cable are needed to connect
the deck to the main cables between the two towers? show all working.
Answered by Penny Nom. |
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Two boats |
2011-11-30 |
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From Shayan:
A boat is traveling 20 miles per hour when it passes a lighthouse.
another boat is traveling at 15 miles per hour when it passes a point.
the lighthouse and the point are 175 miles apart.
when will the boats pass each other?
Answered by Penny Nom. |
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The 3rd term of an A.P is 10 more than the first term |
2011-11-29 |
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From Olaniyan:
the 3rd term of an A.P is 10 more than the first term while the fifth term is 15 more than the second term. Find the sum of the 8th and 15th terms of the A.P if the if the 7th term is 7 times the first term.
Answered by Penny Nom. |
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Three consecutive numbers |
2011-11-29 |
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From Michael:
Find three consecutive numbers such that the second number squared
is equal to the first and third added together
Answered by Penny Nom. |
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Converting from base 4 to base 10 |
2011-11-29 |
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From anjg:
How to convert base 4 number 2^11 to base 10 number?
Answered by Penny Nom. |
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An arithmetic expression |
2011-11-28 |
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From Muhmmad:
2/5*-3/7-1/6*3/2+1/14*2/5
Answered by Penny Nom. |
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