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the shizzle => shootin' the shit => Topic started by: rich d on January 21, 2013, 07:01:40 pm

Title: Rearranging an equation
Post by: rich d on January 21, 2013, 07:01:40 pm

I'm having a blonde moment and can't get anywhere, can the wise of UKB help.
Also found I can't write the equation properly on here so bear with me
Z= r - square route of r squared -y squared
R squared -y squared are both under the square route
I need to calculate y
Sorry that is so poorly written - stupid bloody iPad...
Thanks rich

Title: Re: Rearranging an equation
Post by: JonWells on January 21, 2013, 07:18:44 pm

assuming i read it right:

z = r - sqrt(r² - y²)
sqrt(r² - y²) = r - z
r² - y² = (r - z)²
y² = r² - (r² - 2rz + z²)
y² = 2rz - z²

y = sqrt(2rz - z²)

hope that helps

Title: Re: Rearranging an equation
Post by: rich d on January 21, 2013, 07:23:05 pm

Lovely thanks

Title: Re: Rearranging an equation
Post by: aLICErOBERTSfANkLUB on January 22, 2013, 10:01:33 pm

"sqrt"

Fnarr-fnarr!

(http://amodernmilitarymother.com/wp-content/uploads/2010/08/finbarr-saunders.jpg)

Title: Rearranging an equation
Post by: tomtom on January 22, 2013, 10:29:59 pm

Square root might raise a titter down under fnarr fnarr

Title: Re: Rearranging an equation
Post by: aLICErOBERTSfANkLUB on January 23, 2013, 03:32:21 pm

GPWM.