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#27 Re: Help Me ! » Linear functions and Matrices » 2011-10-06 23:51:35

Just a wild guess, but would you sub the values of x and y into the first equation?

#28 Re: Help Me ! » Linear functions and Matrices » 2011-10-06 23:34:28

ah, sorry. I'll have to keep that in mind.

Ok so would I now use this to substitute back into the equation and solve for a?

#32 Re: Help Me ! » Linear functions and Matrices » 2011-10-06 22:58:01

oops, yes I should have done that.

From this point would I need to substitute this equation into the first equation, and then solve for a?

#34 Re: Help Me ! » Linear functions and Matrices » 2011-10-06 22:43:55

ok that makes sense.
Not really sure what I need to do now though...

#35 Re: Help Me ! » Linear functions and Matrices » 2011-10-06 22:34:57

I'm not sure but is it;

2x+5y-ax-2ay+2a=3

ay-3y=3

Edit: oh ok, I see that I wasn't supposed to expand it.

#37 Re: Help Me ! » Linear functions and Matrices » 2011-10-06 22:18:19

So, would it be wrong if I removed x and solved for z in the first equation and got

z=2y+2 ?

#38 Re: Help Me ! » Linear functions and Matrices » 2011-10-06 22:07:45

I'll try; do I arrange them for y?

#39 Re: Help Me ! » Linear functions and Matrices » 2011-10-06 21:57:06

Okay that cleared some stuff up, so would I start off by rearranging the three equations?

Sorry, I'm really terrible at these questions.

#40 Help Me ! » Linear functions and Matrices » 2011-10-06 20:59:28

Marisca
Replies: 37

Hi, I'm having trouble with these questions and was wondering if anyone could help:

Consider the system of equations;
x+2y-z=2
2x+5y-(a+2)z=3
-x+(a-5)y+z=1

a) Solve the equations in terms of 'a', for suitable values of 'a'.
b) State the values of 'a' for which there is a unique solution.

Is this the type of question where I would need to set the three equations as matrices?

#41 Re: Help Me ! » Probability help needed... » 2011-07-06 01:01:10

Hello, no it was right.

Thanks for helping gAr; post #1 was the same question.

#42 Re: Help Me ! » Probability help needed... » 2011-07-04 02:52:35

Bayes theorem? I've actually never heard of that.
No matter, I'll look it up later tonight smile Thank you so much for helping!

#43 Re: Help Me ! » Probability help needed... » 2011-07-04 02:16:10

Yep, that's right.
The second should be 5/14

#45 Re: Help Me ! » Probability help needed... » 2011-07-04 02:07:24

If you're referring to the above question, then no that's there was. However, there is a separate part of that question which asks.

"If one bowl is chosen at random and from it one piece of fruit is chosen at random without replacement. Find the probability that the fruit chosen is an apple."
and that..
"...if the piece of fruit chosen was an apple. Find the probability that A was the chosen bowl".

#47 Re: Help Me ! » Probability help needed... » 2011-07-04 01:46:33

That's weird, my text book shows a different answer....

#49 Help Me ! » Probability help needed... » 2011-07-04 00:50:21

Marisca
Replies: 21

Hi, I was having a little trouble with this question, and wondering if anyone could help me?
two bowls each contain 10 pieces of fruit. In bowl A there are 5 oranges and 5 apples, in bowl B there is 1 orange and 9 apples.
With no replacement AND replacement;  find the probability that two pieces of fruit chosen will both be apples?

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