[libstar]

Hi does anyone know how to make y the subject?

s = r square root sign [r squared - y squared]??

been stuck for a while any help would be great xx

[phil207]

so s = r√[r^2 - y^2]

first square everything, to eliminate the square root, so...
s^2 = r^2 [r^2 - y^2]

then simple re-arranging
s^2 / r^2 = r^2 - y^2

and y^2 = [s^2/r^2] - r^2

then square root the whole left hand side to get y=,.

y = √ ([s^2/r^2] - r^2)

I think this is right, let mew know what you think

[phil207]

wait, mistake!!

y^2 = r^2 - [s^2/r^2]

then square root the whole left hand side to get y=,.

y = √ (r^2 - [s^2/r^2])

this is better and righter