CPhill

Re: how do i solve 2 1/4 x 3 2/3 ----------------------------------------------------------------------------------------------------------------------------

Let's convert each mixed number to an improper fraction.......we have

9/4 x 11/3      Notice that we can "cross-cancel" the "9" with the "3"      This gives us

3/4 x 11/1 = 33/4 = 8 1/4

It's always nice if you can "cancel" before you multiply....it usually saves some work, later

Also, you could use the on-site calculator to do this...just make sure that you put parentheses around both mixed numbers.  The calculator will give you the answer in both fractional and "mixed form" - if the result has a "mixed form."

To be honest, I kinda' struggled with it, too. I don't "do" 3-D as well as "2-D," so if I can lay something out in terms of area, it usually helps me see its volume....basically, my answer was just me "thinking aloud!!!" I believe it's correct, but  Alan, Rom or Bertie  - or someone else - might verify it (or not)!!!

Assuming they're in the same time zone - and I think they are...... 2 hrs 15 min

Re: 4a+5b=7,b=8

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This says we are just letting b=8 and then trying to find "a"

OK....so

4a + 5(8) = 7

4a + 40 = 7    subtract 40 from both sides

4a = -33          divide both sides by 4

a = -33/4

That's it !!   You should check this answer in the original equation to make sure it's true.

Yep...from me.......I always like to get feedback, too. I'm not always correct - or even precise - with my answers, but I try hard. One thing this board has taught me.......you can't just throw something imprecise out there.......but that's a good thing.....it makes you think a little more about the answers you give!!!

Yeah...a "sea food" diet......I "see food" and I have to eat it !!!

Re: what is the square root of 4?

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I believe the standard convention is to take the positive root (2), unless we're solving equations. For instance,

x² = 4

√x² = √4

x = ± 2

Note that the square root of 4 here has two values.

Nope....looks fine to me........we can find a way to do it - algebraically - just not "geometrically" without "cheating." It's the "pi" that gives us problems.....

Of course....."pi" (pie) always gives me problems!!!

Well....there's an old expression that I always like concering two or more people getting the same answers through different methods......

......You and I might mow your yard in different ways, but in the end, it all looks pretty much the same !!!

How can I build a circle which must have the same area as a given square ?

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"Squaring" the circle......a problem that the "ancients" were fascinated with!!!

I'm not an "expert" on this - some people on this site are probably far more knowledgeable about it - but it can't be done with standard "Euclidean" tools....i.e., compass and straightedge.

There HAVE been examples of people constructing various "curves" - a "lune," for instance -that equal the area of a given square.........(but they had to "cheat" to do it, as I understand)

I found something about this here.......it's quite interesting !!

http://en.wikipedia.org/wiki/Squaring_the_circle