A line has a slope of $\displaystyle-{3}\usepackage{cmbright}\Huge\$ , so its equation has the form $\displaystyle{y}=-{3}{x}+{b}\usepackage{cmbright}\Huge\$ . The line passes through the point $\displaystyle{\left({1},-{2}\right)}\usepackage{cmbright}\Huge\$ . What is the y-intercept, b, of the line?

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