The equation of a line perpendicular to another line always has an opposite and reciprocal slope. For this equation here, the opposite and reciprocal slope of 2x is -1/2x. This is because 2 becomes negative (-2) and it is flipped from the numerator (-1/2). So, our equation so far is y = -1/2x + b. B represents the y-intercept. And since we already know the y-intercept, all we have to do is plug it in! Here is our finished equation: y = -1/2x - 2.
