I'd like to be able to express the following in a graph:
Given the equation $a=y(1-x)$ where $0 \leq x,y \leq 1$ and three class thresholds:
A: a<0.05
B: 0.05<a<0.1
C: a>=0.1
I'd like to show that the a sample $(y=1, x=0.7)$ falls under class C $(y=0.3)$ and under the class C curve.
How would I graph all 3 trendlines (classes) and the sample in a single graph in Excel or Python?