Am I doing this the right way? Is there a faster way of doing this? Thanks. You're doing this exactly the right way. No, I'm not familiar with any "faster" way. Just keep going like you are. You have found that T must be 2 or 4. Each of these options is a "case". So test the &qu...

- on Mon Dec 08, 2008 6:17 pm
- Forum: Arithmetic
- Topic: THINK + RETHINK = REFLECT (each letter stands for a number)
- Replies:
**2** - Views:
**4463**

I think this gives me y^2 - 7y - 8 = 0. Is that right? That's exactly right! :wink: Now factor, and set each factor equal to zero. Once you've done that, plug the 2^x back in for the y, and use what you know about powers to find the answers. If you get stuck, please reply showing how far you got. T...

- on Mon Dec 08, 2008 6:29 pm
- Forum: Beginning Algebra
- Topic: Solve 2^(2x) - 7(2^x) - 8 = 0 (Hint: Let y = 2^x)
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**3659**

My thinking: Since the average of the 8 numbers is 3, and you find this average by dividing the total by 8, then that total is 8*3 = 24, right? So would the total of the others be 12*x, with the combined total being 20*9 = 180? And then you add the two smallers numbers and make this equal to the co...

- on Tue Dec 09, 2008 9:40 pm
- Forum: Statistics
- Topic: mean of 8 numbers is 3, mean of 12 is x, mean of all is 9
- Replies:
**2** - Views:
**3835**

little_dragon wrote:Is this the right way to set it up? Do I do the trig ratios and use my calculator to find how tall he is?

Sounds good to me!

Eliz.

- on Wed Dec 10, 2008 12:36 am
- Forum: Trigonometry
- Topic: angle of depression and how tall is romeo
- Replies:
**1** - Views:
**4200**

They've given you the first three factors at the beginning, but only one at the end. Try writing out the factors from the end, working backwards from (x - z)....

Eliz.

Eliz.

- on Wed Dec 10, 2008 6:27 pm
- Forum: Discrete Math
- Topic: find value of (x - a)(x - b)(x - c) ... (x - z)
- Replies:
**2** - Views:
**5044**

It would appear that the "Pre" tags work better than the "code" tags...?

At least, I can certainly read the results better!

Eliz.

At least, I can certainly read the results better!

Eliz.

- on Wed Dec 10, 2008 7:35 pm
- Forum: Forum Rules & Guides
- Topic: trying out some of the formatting
- Replies:
**4** - Views:
**4870**

This answer works, but it seems too easy. Am I doing this wrong? You're only "doing it wrong" if you were told to use some particular other method (such as a system of equations). :wink: What you have done is logical, and it leads to the correct answer. I would think that, as long as you ...

- on Sun Dec 14, 2008 1:41 pm
- Forum: Pre-Algebra
- Topic: find normal and overtime rates of pay for carpenter
- Replies:
**3** - Views:
**4819**

LateX (pronounced "LAY-teck"): . . . . . [t ex]\left[ \begin{array} {rrr} 1&2&3 \\ 4&5&6 \\ 7&8&9 \end{array} \right][/tex] ...produces: . . . . . \left[ \begin{array} {rrr} 1&2&3 \\ 4&5&6 \\ 7&8&9 \end{array} \right] ...while: . . . . . [pre...

- on Sun Dec 14, 2008 1:58 pm
- Forum: Matrix (Linear) Algebra
- Topic: formatting matrices using LaTeX and 'pre' tags
- Replies:
**0** - Views:
**2736**

36: Find the limit: lim, x -> 0, (sin 4x)/(sin 6x) I'm pretty sure I need to use the fact that lim, x->0, (sin x)/(x) = 1.... You're exactly right about the tool you need to use. There's a bit of a trick to setting it up, though. For the moment, let's leave off the "limit" bit, and just d...

- on Mon Dec 15, 2008 1:43 am
- Forum: Calculus
- Topic: find limit of (sin 4x) / (sin 6x) as x goes to zero
- Replies:
**2** - Views:
**8193**

This would make the two ends meet up at (x, y) = (4, 12). Is that okay? I'm not forgetting any "calculus" stuff for this, am I? I'm not familiar with any extra, calc-specific stuff that you "should" do in addition to what you've done. And your value for "c" makes the t...

- on Tue Dec 16, 2008 12:32 pm
- Forum: Advanced Algebra ("pre-calculus")
- Topic: find the constant c that makes g continuous (g in two parts)
- Replies:
**1** - Views:
**5991**