Question: what is the equation of a line that is perpendicular to y=2x+4?
Answer: The slope-intercept form is y=mx+b y = m x + b , where m m is the slope and b b is the y-intercept. Using the slope-intercept form, the slope is 2 2 . The equation of a perpendicular line to y=2x+4 y = 2 x + 4 must have a slope that is the negative reciprocal of the original slope.