# make s subject

• Nov 17th 2009, 02:41 PM
decoy808
make s subject
make s subject

t = v√$\displaystyle s^2$+9

this is what im at help me if you can. many thanks

√$\displaystyle t^2$/v-9 = s
• Nov 17th 2009, 03:02 PM
pickslides

$\displaystyle t = v\sqrt{s}^2+9$

then it can be re-written as

$\displaystyle t = vs+9$

as the square ad square root are opposites.

Now taking 9 from both sides

$\displaystyle t-9 = vs$

$\displaystyle vs= t-9$

and dividing v

$\displaystyle s= \frac{t-9}{v}$

now s is the subject.
• Nov 18th 2009, 12:40 AM
decoy808
im having problems geting the correct value.

the first part of the question was to find V? which i found to be 2

V= 2
T=10
S= 4

so making s the subject i should get answer 4?
s= t-9/v
4 = 10-9/2
• Nov 18th 2009, 01:07 AM
aidan
Quote:

Originally Posted by decoy808
make s subject
t = v√$\displaystyle s^2$+9
this is what im at help me if you can. many thanks
√$\displaystyle t^2$/v-9 = s

It looks as if you meant this:

$\displaystyle t = v \sqrt{s^2 + 9 }$

then to make s the subject:

$\displaystyle s = \sqrt{ \left( \dfrac{t}{v} \right)^2 - 9}$

$\displaystyle s = \sqrt{ \left( \dfrac{10}{2} \right)^2 - 9}\,\, = 4$