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How would I solve this?

Simplify radcial expressions:

1. (2+squareroot5) (3-squareroot5)

2. 3 squareroot 48 - 2 squareroot75
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Squareroot 12

I will step you through the last one to show you how. Then you apply it to others. OK?

$\frac{3\sqrt{48}-2\sqrt{75}}{\sqrt{12}}$

$\frac{3\sqrt{16\cdot{3}}-2\sqrt{25\cdot{3}}}{\sqrt{4\cdot{3}}}$

See how we have $\sqrt{3}$ common to all the terms? Those are the kinds of patterns we look for.

$\frac{3\sqrt{16}\cdot\sqrt{3}-2\sqrt{25}\cdot\sqrt{3}}{\sqrt{4}\cdot\sqrt{3}}$

$\frac{12\sqrt{3}-10\sqrt{3}}{2\sqrt{3}}$

$\frac{2\sqrt{3}}{2\sqrt{3}}=1$

And that's it. Whittled down to a very simple answer. Now, you try on the other.

3 squareroot 5 + 5 squareroot 6 + 3 squareroot 20