Melody

18 shows growth because as x gets bigger so does y.

26. You will use the compound interest formula     PV=P(1+r)^n

That is a start for you anyway. 

Do you mean that this is an irregular pentagon (5 sides)

And that the distance from some central point to each of the vertices is the lengths given?

No I don't think that is what you mean.  

No I'm sorry i do not know what you mean.

okay thanks Alan.  

I don't think that is quite right Takahiro,

Say something costs $100 and you have to add 10%gst that makes it cost $110.

If you want to go backwards you cannot say 10% of $110=$11 so the pre GST price was 110-11=$99.

You see, it is 10% of the pre taxed price not 10% of the hight price!

--------------------------

I am going to let the original price be $x

It was reduced by 20% so the new price will be 80% of the original price.  That is 0.8x

Now 10% GST is added that means the price will  be 110% of 0.8x = 1.1*0.8x = 0.88x

Nlow 0.88x=$120

x=120/0.88

x=$136.36 to the nearest cent.  

What are all these little pictures that are appearing that I can't see.  They are annoying.

The quantity of time measured in minutes depends on the quantity of speed measured in feet.

The quantity of speed measured in feet depends on the quantity of time measured in minutes.

Speed is not measured in feet!    So it is not either of those 2.  

The quantity of distance measured in feet depends on the quantity of time measured in minutes.

The quantity of time measured in minutes depends on the quantity of distance measured in feet.

Now this is strange wording but the distance the plane travels depends on how many minutes have passed.

Plus speed = distance / time 

So I would go for the 2nd last one. 

This is a tricky one maria,

69 = half of 2 adult tickets + half of 1 child's ticket

69 = 1 adult tickets + half of 1 child's ticket

Let the adults ticket be x dollars

The child ticket is 6 dollars less so that would be x-6

so

$$\\69 = x + \frac{1}{2}(x-6)\\\\
\mbox{multiply both sides by 2}\\\\
138=2x+(x-6)\\
138=2x+x-6\\
138=3x-6\\
144=3x\\
x=48 \qquad \mbox{Price of full adult ticket}\\
Child =48-6=\$42$$

NOTE TO MARIA379

Your questions include pictures that do not display on my computer.  Can you insert whatever these are by hand please?

4x - 3y + 2z - 3x - y + 3z = ?

When you add and subtract with algebra you can think of the pronumerals as things.

You can only add and subtract like terms - this means the 'things' must be the same.

so you can think of this problems as

4 xylophones - 3 yaks + 2 zebras - 3 xylophones - a yaks + 3 zebras

=4 xylophones  - 3 xylophones - 1 yaks - 3 yaks + 3 zebras + 2 zebras

=1 xylophones   - 4 yaks  + 5 zebras 

=1x-4y+5z

=x-4y+5z         (1 xylophone is the same as a xylophone - you don't need the 1 it can be invisable)

Thanks for the laughs Rosala.  

I just did a page of LaTex for this (which I lost) and I am not going to repeat it BUT

Here is a page that I put together on negative indices.  It should help you understand how it works.