A line has a slope of $\displaystyle\frac{{2}}{{5}}\usepackage{cmbright}\Huge\$ and contains the point $\displaystyle{\left(-{10},-{6}\right)}\usepackage{cmbright}\Huge\$ .

What is the y-intercept (b) of the line?

$\displaystyle{b}=\usepackage{cmbright}\Huge\$ _____