# What is sqrt(50)-sqrt(18)?

Mar 5, 2018

$2 \sqrt{2} \approx 2.83$

#### Explanation:

$\sqrt{50} - \sqrt{18} = \sqrt{25 \cdot 2} - \sqrt{9 \cdot 2} = \sqrt{{5}^{2} \cdot 2} - \sqrt{{3}^{2} \cdot 2}$
$\sqrt{\textcolor{red}{{5}^{2}} \cdot 2} - \sqrt{\textcolor{red}{{3}^{2}} \cdot 2} = \textcolor{red}{5} \sqrt{2} - \textcolor{red}{3} \sqrt{2} = 2 \sqrt{2} \approx 2.83$

Mar 5, 2018

$\sqrt{50} - \sqrt{18}$
= $\sqrt{2 \cdot 25} - \sqrt{2 \cdot 9}$
=$5 \sqrt{2} - 3 \sqrt{2}$
= $2 \sqrt{2}$

#### Explanation:

First you need to find the smallest number these are both divisible by (excluding 1) and write out the equation again with that (in this case it is $\sqrt{2 \cdot 25}$ for the first one and $\sqrt{2 \cdot 9}$ for the other one.
Then you need to find the square root of the larger number and then it is that multiplied by the root (so again in this case it is now =$5 \sqrt{2} - 3 \sqrt{2}$.
Finally you just subtract the two surds leaving you with the answer - $2 \sqrt{2}$.
Hopefully this helped you! :)