Line L has equation 2x - 3y = 5. Line M passes through the point (2, -10) and is perpendicular to line L. Determine the equation for line M.
can you solve -> 2x - 3y = 5. <- for "y" ? what would that give you?
y=2x/3−5/3
so....notice the slope of that line \(\bf y={\color{blue}{ \cfrac{2}{3}}}x-\cfrac{5}{3}\) thus is 2/3 well, the slope of a line that is perpendicular to the line of that equation will have a NEGATIVE RECIPROCAL slope that is \(\bf {\color{blue}{ \cfrac{2}{3}}}\qquad reciprocal \implies {\color{blue}{ \cfrac{3}{2}}}\qquad negative\implies -{\color{blue}{ \cfrac{3}{2}}}\) so the equation for line M will be the equation of a line that passes through (2, -10) and has a slope of -3/2 thus \(\bf \begin{array}{lllll} &x_1&y_1\\ &({\color{red}{ 2}}\quad ,&{\color{blue}{ -10}})\quad \end{array} \\\quad \\ slope = {\color{green}{ m}}= -\cfrac{3}{2} \\ \quad \\ y-{\color{blue}{ y_1}}={\color{green}{ m}}(x-{\color{red}{ x_1}})\qquad \textit{plug in the values and solve for "y"}\\ \qquad \uparrow\\ \textit{point-slope form}\)
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