When you use the slope formula, $\displaystyle{m}=\frac{{{y}_{{2}}-{y}_{{1}}}}{{{x}_{{2}}-{x}_{{1}}}}\usepackage{cmbright}\Huge\$ , be careful to subtract in the same order in the numerator and denominator. That is, the first numbers on top and bottom should be the coordinates from the same point. The slope of this line is given by: $\displaystyle\frac{{{3}-{\left(-{2}\right)}}}{{{6}-{\left(-{4}\right)}}}\usepackage{cmbright}\Huge\$