Find the points on the curve at which the tangent is
perpendicular to the straight line .
First, find the slope function of the curve by differentiating.
The equation of the straight line can be rearranged to
and therefore its slope is .
If the tangent is perpendicular to this line, then its slope will be .
Now set the slope function equal to 7 and solve for .
Finally, find the -coordinates on the curve for each value.
Therefore, the coordinates of the two points where the tangent is perpendicular to the straight line are and .