Melody

Hi anonymous,

You have solve the queston but you have done it by substitution. 

The question stipulated 'elimination method'.

But I am really glad that you answered.  I like people to get involved.   

The circle that forms the wheel of fortune from Beijing in China has a perimeter of 621.72 meters. What is the area of the circle of the wheel of Fortune? Consider π = 3.14

$$P=2\pi r\\\\
621.72=2\times 3.14\times r\\\\
r=\frac{621.72}{6.28}\\\\
r=99 \mbox{ metres}$$

$$A=\pi r^2\\\\
A=3.14\times 99^2$$

And you can finish it!  

Yes - Spooky

All of anything is 100%

If you decreade it by 73% then you must want 100-73=27%

27%of 900 = 27/100*900 = 243 

Hi Chris,

The web address contained the actual question - I guess that is why my answer seemed a bit strange to you. 

per means divide

So you take the number of miles you have traveled and divide it by the number of hours that it has taken.

that will give you the average speed in miles per hour ( miles/hour)

another notation is

$$^{13}C_4$$    You can get the answer straight from your calculator.

CPhill is right.

THE INVERSE OF A FUNCTION IS THE EQUATION OF THE FUNCTION'S IMAGE WHEN IT IS REFLECTED ABOUT THE LINE Y=X     (This is important to know)

I just swap the letters around right from the beginning and then rearrange

y=5x+6 becomes

x=5y+6

$$y=\frac{x-6}{5}\\\\
f^{-1}(x)=\frac{x-6}{5}\\\\$$

Talking about right and left always confuses me.

If it is a big number the power is positive.

If it is a little number (less than 1) then the power is negative.

Easy Peazy

70,000 is definitiely a big number!

You might find it easier if you replace the x² with y

then you have y²+3y+2

You need two numbers that multiply to 2 and add to 3. they'll be 2 and 1

(y+2)(y+1)    but y=x²

(x²+2)(x²+1)