Simplify 3x square root of 25x-9x square root of 4x-3x square root of x

$3 x \sqrt{25 x} - 9 x \sqrt{4 x} - 3 x \sqrt{x}$

Simplify each term.

Rewrite $25$ as $5^{2}$ .

$3 x \sqrt{5^{2} x} - 9 x \sqrt{4 x} - 3 x \sqrt{x}$

Pull terms out from under the radical.

$3 x (5 \sqrt{x}) - 9 x \sqrt{4 x} - 3 x \sqrt{x}$

Multiply $5$ by $3$ .

$15 x \sqrt{x} - 9 x \sqrt{4 x} - 3 x \sqrt{x}$

Rewrite $4$ as $2^{2}$ .

$15 x \sqrt{x} - 9 x \sqrt{2^{2} x} - 3 x \sqrt{x}$

Pull terms out from under the radical.

$15 x \sqrt{x} - 9 x (2 \sqrt{x}) - 3 x \sqrt{x}$

Multiply $2$ by $- 9$ .

$15 x \sqrt{x} - 18 x \sqrt{x} - 3 x \sqrt{x}$

Simplify by adding terms.

Subtract $18 x \sqrt{x}$ from $15 x \sqrt{x}$ .

$- 3 x \sqrt{x} - 3 x \sqrt{x}$

Subtract $3 x \sqrt{x}$ from $- 3 x \sqrt{x}$ .

$- 6 x \sqrt{x}$