Alan

Let R be the number of feet of Redwood he needs and P be the number of square feet of Plywood.

From store A:     2.59*R + 0.99*P = 2990.26

From store B:     0.99*R + 1.09*P = 2879.16

From B:  R = (2879.16 - 1.09*P)/0.99   ...(C)

Put this into A:   2.59*(2879.16 - 1.09*P)/0.99 + 0.99*P = 2990.26

2.59*2879.16/0.99 - 2.59*1.09*P/0.99 +0.99*P = 2990.26

Can you take it from here?  (Find P from this then insert the result in C above to find R)

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You can't upload images while you are Anonymous, so we can't see your picture.  Register in order to do so (or describe the problem in words or symbols from the "Insert" menu).

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Take logs of both sides

log(5^x) = log(17)

Use the property of logarithms that states log(a^b) = b*log(a)

x*log(5) = log(17)

x = log(17)/log(5)

$${\mathtt{x}} = {\frac{{log}_{10}\left({\mathtt{17}}\right)}{{log}_{10}\left({\mathtt{5}}\right)}} \Rightarrow {\mathtt{x}} = {\mathtt{1.760\: \!374\: \!427\: \!722\: \!587\: \!7}}$$

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-3 1/4 is -13/4 so 

-(13/4)*x = 2

Multiply both sides by 4

-13*x = 8

Divide both sides by -13

x = -8/13

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The median is the middle value when the items are sorted into ascending order.  If there are an even number of terms the median is the mean of the two middle values.

e.g   1 2 3     the median is 2

 1 2 3 4        the median is (2 + 3)/2 = 2.5

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Test of picture upload:

Seems to have uploaded ok

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As x → ∞  then  x-1 → x, so:

$$\lim_{x\rightarrow \infty}(x^\frac{1}{2}-(x-1)^\frac{1}{2})=0$$

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Re:  The picture (a graph) disappeared!

Try uploading it again in 30 minutes or so.  I've also noticed occasional hiccups with uploading images.

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Do you mean sin3x*cos2x + cos3x*sin2x?  If so this simplifies to sin(5x).

As written, the original doesn't simplify much, though it can be written as (sin²5x - sin²x)/4 

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Use the calculator here.  Enter 7^7 

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