To find the first derivative of (2-3x)5 with respect to x.

The problem asks to find the first derivative of $(2-3x)^5$ with respect to $x$.
Let $y = (2-3x)^5$.

The chain rule states that if $y = f(g(x))$, then $\frac{dy}{dx} = f'(g(x)) \cdot g'(x)$.
In this case, let $g(x) = 2-3x$ and $f(u) = u^5$, where $u = g(x)$.

If $f(u) = u^5$, then $f'(u) = \frac{d}{du}(u^5) = 5u^{5-1} = 5u^4$.

If $g(x) = 2-3x$, then $g'(x) = \frac{d}{dx}(2-3x) = \frac{d}{dx}(2) - \frac{d}{dx}(3x) = 0 - 3 = -3$.

The first derivative of $(2-3x)^5$ is $\boxed{-15(2-3x)^4}$.