The function is
, and parallel line equation is
.
Definition of slope of the tangent line :
.
Slope of the tangent line is
.
Parallel line equation is
.
Find the slope of the parallel line
.
Slope of the line
is
.
.
The line is parallel to the tangent line then their slopes are equal.
\Equate the slope of the tangent line to
.

Substitute
in function
.

The point on the curve is
.
Find the equation of the tangent line.
\Point-slope of line equation :
.
Substitute
and point
in the point slope form.


Equation of tangent line is
.
Equation of tangent line is
.