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A triangle with two equal medians |
2009-12-19 |
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From Nazrul:
If two medians of a triangle are equal , how can I prove that the triangle is isosceles.
Answered by Chris Fisher. |
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How much will i have saved in that year? |
2009-12-18 |
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From Loretto:
If i save a penny and it doubles every day for one year how much will i have saved in that year
Answered by Robert Dawson. |
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Houses on a triangular field |
2009-12-18 |
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From Beth:
Hi, this is the question i have to answer.
Planning permission has been granted to build houses on the triangular field in the diagram. The housing density permitted is 1 house for each 200m². Calculate how many houses can be built on this
Beth
Answered by Robert Dawson. |
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Polygons, diagonals and the sum of the measures of the angles |
2009-12-18 |
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From jason:
find the set of polygons in which the number of diagonals is greater than the sum of the measures of the angles
Answered by Robert Dawson. |
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A ball is thrown upwards |
2009-12-17 |
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From Reuben:
A ball is h meters above the ground t seconds after it is thrown where
h(t) = 40t – 5t ^2 . Find the time at which the ball first reaches a height of
(a) 10 meters
(b) 40 meters
(c) 100 meters
Answered by Harley Weston. |
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Maximizing the area of a rectangle |
2009-12-17 |
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From rachel:
A rectangular field is to be enclosed by 400m of fence. What dimensions will give a maximum area?
Answered by Penny Nom. |
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The acute angle formed by intersecting lines |
2009-12-17 |
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From Katie:
To the nearest tenth of a degree, find the size of the acute angle formed by the intersecting lines 3x + 2y = 12 and x - 2y = -2. Was is necessary to find the intersection point?
Answered by Robert Dawson. |
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A pile of sand |
2009-12-16 |
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From Malik:
Sand is leaking out of a hole at the bottom of a container at a rate of 90cm3/min. As it leaks out, it forms a pile in the shape of a right circular cone whose base is 30cm below the bottom of the container. The base radius is increasing at a rate of 6mm/min. If, at the instant that 600cm3 have leaked out, the radius is 12cm, find the amount of leakage when the pile touches the bottom of the container.
Answered by Harley Weston. |
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A trig question |
2009-12-15 |
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From A trig question:
Hey, my name is Candle
I'm in academic math10 and am stuck on my trig... one question I thought I had right because i used the cosine law I got wrong and can't figure out why... here's a copy of the question. (i guessed it was D... but my teacher said it's B)
Thanks
Candle
Answered by Robert Dawson. |
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Percentage reduction |
2009-12-15 |
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From John:
Please explain how I should calculate the percentage of £676 billion reduced to £498billion
Answered by Harley Weston. |
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Energy in calories |
2009-12-15 |
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From Josephine:
A soft drink manufacturer claims that a new diet soft drink is now "low Joule". The label indicates that the available energy per serving is 6300 J. What is the equivalent of this energy in calories? (1 Calorie=1000 cal)
Answered by Robert Dawson. |
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A 4 digit number |
2009-12-15 |
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From Lisa:
Billy Club was assigned the task of putting numbers on
all the playground balls used during daily recess. Billy
will number the balls using the following rules:
1. It will be a 4-digit number.
2. The digit in the thousands place will be a 1 or a 2.
3. The digit in the hundreds place will be a 2, 4, or 6.
4. The digit in the tens place will be an odd number.
5. The digit in the ones place will be greater than six.
How many balls can Billy number if he follows these rules?
Answered by Robert Dawson. |
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The second derivative of y = x³ (x² + 5) |
2009-12-14 |
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From Kyrie:
Find d²y/dx² for this function:
y = x³ (x² + 5)
Answered by Penny Nom. |
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A circle problem |
2009-12-14 |
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From Fawad:
AP is a tangent at P to a circle centre O, where AP=6cm. The straight line AQC is such that QC= 9cm.
Find the length, in cm of AQ.
Answered by Chris Fisher. |
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A telephone pole on a slope |
2009-12-14 |
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From Marissa:
A 10 meter telephone pole casts a 17 meter shadow directly down a slope when the angle of elevation of the sun is 42 degrees. Find the angle of elevation of the ground. Its a law of sines problem.
Answered by Penny Nom. |
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