# How do you simplify (sqrt2-3)(sqrt2+3) ?

Distribute the one expression over the other, then add the resulting terms together, to get to $- 7$

#### Explanation:

$\left(\sqrt{2} - 3\right) \left(\sqrt{2} + 3\right)$

Now let's distribute the one over the other. I'll list the answers below:

$\sqrt{2} \cdot \sqrt{2} = 2$
$\sqrt{2} \cdot 3 = 3 \sqrt{2}$
$- 3 \cdot \sqrt{2} = - 3 \sqrt{2}$
$- 3 \cdot 3 = - 9$

We can now add them up:

$2 + 3 \sqrt{2} - 3 \sqrt{2} - 9$

The square root terms subtract against each other and so drop off. We're left with $2 - 9 = - 7$