Simplify sqrt(20)

We can rewrite 20 as a product of a perfect square and another number: $20 = 4 \times 5$.

$$\sqrt{20} = \sqrt{4 \times 5} = \sqrt{4} \times \sqrt{5} = 2\sqrt{5}$$

Replace $\sqrt{20}$ with $2\sqrt{5}$ in the original expression:

$$14(2\sqrt{5}) - 8(2\sqrt{5}) - 10\sqrt{5}$$

Since all terms now have $\sqrt{5}$, we can combine their coefficients:

$$(28 - 16 - 10)\sqrt{5}$$

$$(12 - 10)\sqrt{5}$$ $$2\sqrt{5}$$