1. ## Rearrange

Hi jus a little help. Good someone show me the steps for rearranging the following equation in terms of 'u' please:

164 = u + 8 - 0.5 * 0.5 * (8^2)

?

2. Originally Posted by taurus
Hi jus a little help. Good someone show me the steps for rearranging the following equation in terms of 'u' please:

164 = u + 8 - 0.5 * 0.5 * (8^2)

?
Let's simplify a bit first...

$\displaystyle 164 = u + 8 - (0,5 \times 0,5 \times 64)$

$\displaystyle 164 = u + 8 - 16$

$\displaystyle 164 - 8 + 16 = u$

$\displaystyle 164 + 8 = u$

$\displaystyle u = 172$

EDIT: This is my 5th post

3. ## got another one

i got another one im a bit confused on:
(to get u)

10 = 0.5 * 9.81 * ((40/u)^2)

now wat i tried was:

10 = 4.91 * ((40/u)^2) -------------------- (0.5 * 9.81)

then i got a bit confused there, do i square root it all or wat?

4. Originally Posted by taurus
i got another one im a bit confused on:
(to get u)

10 = 0.5 * 9.81 * ((40/u)^2)

now wat i tried was:

10 = 4.91 * ((40/u)^2) -------------------- (0.5 * 9.81)

then i got a bit confused there, do i square root it all or wat?
$\displaystyle 10 = 0,5 \times 9,81 \times ( \frac{40}{u} )^2$

$\displaystyle 10 = 4,905 \times \frac{1600}{ u^2 }$

$\displaystyle \frac{1600}{ u^2 } = 2,04$

$\displaystyle \frac{1600}{2,04} = u^2$

$\displaystyle 784,8 = u^2$

$\displaystyle u = 28,01$