Find the equation of the tangent line to the curve y = x2 – 2x + 7 which is
perpendicular to the line 5y – 15x = 13.
slope of given line is 3
finding the slope of the tangent by differentiating the curve
m(tangent) = 2x – 2
since both lines are perpendicular to each other
(2x – 2) × 3 = – 1
since this point lies on the curve, we can find y by substituting x
therefore, the equation of the tangent is