Question

obtenha a equação geral da reta r que passa pelo ponto p (-7,-5) é é perpendicular a reta s:3x+y-5=0​

Answer 1

$\large\boxed{\begin{array}{l}\rm s:3x+y-5=0\longrightarrow m_s=-\dfrac{3}{1}=-3\\\\\rm r\perp s\iff m_r\cdot m_s=-1\\\rm m_r\cdot (-3)=-1\\\rm m_r=\dfrac{1}{3}\\\\\rm y=y_0+m(x-x_0)\\\rm y=-5+\dfrac{1}{3}(x-(-7))\\\\\rm y=-5+\dfrac{1}{3}(x+7)\\\\\rm y=-5+\dfrac{1}{3}x+\dfrac{7}{3}\bullet(3)\\\\\rm 3y=-15+x+7\\\rm r:x-3y-8=0\end{array}}$