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A riddle |
2003-11-19 |
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From Sarah:
Ok, our teacher gave us this riddle, and I cannot for the life of me figure it out. He said that there are three problems with the following proof:
Answered by Penny Nom. |
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Systems of equations |
2003-11-19 |
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From Scott:
I hope that u can help me....I
am a college student taking a class in Pre Calculus.....I have homework
due this Friday and it counts a BIG Percentage on my FINAL grade.....I
am getting mixed up and can not figure out a few problems.....Please help
me.....
Method Of Subsitution
Problem 1. y- 8x = -5
x(squared) + y(squared) = 25
Problem 2. y = x(squared) - 2x - 6
Y = x(squared) - 4
Answered by Penny Nom. |
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A point and a line |
2003-11-19 |
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From Meenakshi:
Given a line segment L(x1,y1)
to (x2,y2) and a Point P(x3,y3).
I need the formula to find a point on the line L that is closest to
the point (x3,y3).
Answered by Penny Nom. |
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If 1 is neither prime nor composite... |
2003-11-19 |
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From Joshua:
if 1
is neither prime nor composite...what is it called?
Answered by Claude Tardif and Penny Nom. |
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If 1 is neither prime nor composite... |
2003-11-19 |
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From Joshua:
if 1
is neither prime nor composite...what is it called?
Answered by Claude Tardif and Penny Nom. |
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Unmatched socks |
2003-11-17 |
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From Shannon:
i have 6 pairs of socks lying unmatched in my dresser drawer. Each pair is a differnt color (brown, black, red, yellow, green, purple) When i wake up in the morning, I randomly grab 2 of the loose socks and put them on without looking.
If two socks are randomly selected from the drawer, what is the probability that they match?
Answered by Andrei Volodin. |
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The 4th difference |
2003-11-17 |
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From Jack:
If i had a sequence which was the same at the 4th difference, aka difference
to the 4th, like:
1 5 14 30 56 96
(sequence)
4 9 16 26 40
5 7 10 14
2 3 4
1 1
then what would be the set formulars to find out a, b, c, d, and e
as i know the equation has to be an4+bn3+cn2+dn+e
Answered by Penny Nom. |
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Les 3 maisons |
2003-11-16 |
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From Amandine:
Sur la figure ci-contre on peut voir 3 maisons A, B et C nouvellement construites. Toutes les 3 doivent être reliées au gaz, à l'eau et à l'électricité. Cependant, tous ces raccordements doivent impérativement avoir lieu dans un même plan et les câbles et autres canalisations ne peuvent pas se croiser. Comment doit-on s'y prendre pour relier les 3 maisons à l'eau, au gaz et à l'électricité?
Answered by Claude Tardif. |
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Adding fractions |
2003-11-16 |
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From Ken:
My name is Ken and I am taking my GED course for my High School and have not been in a class for 35 years. I am doing this for re-training. I am at the part about fractions. Here is an example that I am having trouble with.
1 3/7 + 4 2/3 + 11/21
They have no common denominators. Could you PLEASE help me. If you could send me a step by step explanation it would be greatly appreciated.
Answered by Penny Nom. |
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Three problems |
2003-11-16 |
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From Megan:
My name is Megan and I am a junior in high school. Our teacher gave us a few xtra credit questions and I need some help.
Answered by Penny Nom. |
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Divisibility by 7 |
2003-11-14 |
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From A student:
how do you test a number to see if it is divisible by 7 or not?
Answered by Penny Nom. |
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Lines |
2003-11-14 |
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From A student:
What is a name that a group of lines pass through?
Answered by Chris Fisher. |
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root24 = 2 root6 |
2003-11-13 |
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From Burke:
I know that all algerbra can be represented visually, for example: Y=9x+3 is a line on a two dimentional plane. Could Math Central please send me a visual representation of the proccess of simplifying square root like root24 equals 2root6
Answered by Penny Nom. |
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Diagonals in an octagon |
2003-11-13 |
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From Glenn:
Question 1.
What is the probability of choosing the longest diagonal in an octagon? Question 2.
Probability of choosing the shortest?
Answered by Andrei Volodin and Penny Nom. |
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A trig identity |
2003-11-12 |
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From A student:
I can't prove this identity. Can you please help me?
(1-tanx)/(1+tanx)=(1-sin2x)/(cos2x)
Answered by Penny Nom. |
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