Find an equation for the altitude of the triangle shown above . (The altitude of a triangle is perpendicular to its base.) Find the slope of the base. $m_1=$ Find the slope of the altitude. $m_2=$ Use the point-slope formula. Use $m_2$ for the slope, and the vertex of the triangle for $(x_1, y_1)\text{.}$ $$\begin{gathered} y- y_1 = m (x- x_1) \end{gathered}$$ Write your answer in slope-intercept form. $y=$