Expand the terms in the numerator.

The numerator is $5x^2(12x^2+6x) - (4x^3+3x^2) \cdot 10$.
First part:

$$5x^2(12x^2+6x) = (5x^2 \cdot 12x^2) + (5x^2 \cdot 6x) = 60x^{2+2} + 30x^{2+1} = 60x^4 + 30x^3$$

Second part:

$$(4x^3+3x^2) \cdot 10 = (4x^3 \cdot 10) + (3x^2 \cdot 10) = 40x^3 + 30x^2$$

Now substitute these back into the numerator:

$$(60x^4 + 30x^3) - (40x^3 + 30x^2)$$

$$60x^4 + 30x^3 - 40x^3 - 30x^2$$ $$60x^4 + (30x^3 - 40x^3) - 30x^2$$ $$60x^4 - 10x^3 - 30x^2$$

The denominator is $(5x^2)^2$.

$$(5x^2)^2 = 5^2 \cdot (x^2)^2 = 25x^{2 \cdot 2} = 25x^4$$

The expression becomes:

$$\frac{60x^4 - 10x^3 - 30x^2}{25x^4}$$

Divide each term in the numerator by the denominator:

$$\frac{60x^4}{25x^4} - \frac{10x^3}{25x^4} - \frac{30x^2}{25x^4}$$

Simplify each fraction:

$$\frac{60}{25} - \frac{10}{25x} - \frac{30}{25x^2}$$

Reduce the numerical coefficients:

$$\frac{12 \cdot 5}{5 \cdot 5} - \frac{2 \cdot 5}{5 \cdot 5x} - \frac{6 \cdot 5}{5 \cdot 5x^2}$$ $$\frac{12}{5} - \frac{2}{5x} - \frac{6}{5x^2}$$