Given the two points of a line: P1 = (5.3,-4.1) and P2 = (-17.0,9.9) find the slope.

$$ slope,\:m=\frac{\left(9.9-\left(-4.1\right)\right)}{-17-5.3}=\frac{14}{-22.3}=-0.62780269058295964125560538116592 $$