Simplify the following expression:

$$a\sqrt{128}$$

$$=8a\sqrt{2}$$

Decompose the number 128 as a product of two numbers, preferably so that at least one component is a square number (can be written as the square of some number).

Square root decomposition:

$$\sqrt{a\xb7b}=\sqrt{a}\xb7\sqrt{b}$$

$$8a\sqrt{2}$$