Question

write the equation of the line that is perpendicular to the graph of 3x - y = 5, and whose y-intercept is (0,-7)

Answer 1

$\begin{gathered} \text{Isolate y} \\ -y=-3x+5 \\ y=3x-5 \\ \\ Slope\text{ for perpendicular line} \\ \frac{-1}{3} \\ \\ \text{Use values} \\ y=mx+b \\ -7=-\frac{1}{3}(0)+b \\ -7=b \\ \\ \text{Equation of the perpendicular line} \\ y=-\frac{1}{3}x-7 \end{gathered}$