we know that
The centroid of a triangle is the intersection of the three medians of the triangle. The coordinates of the centroid are also two-thirds of the way from each vertex along that segment
so
in this problem
The point G is the centroid of the triangle ABC
------> equation A
we have

substitute in the equation A and solve for x
------> equation B
we have

substitute in the equation B and solve for GF
substitute the value of x
therefore
the answer is
She used
, but the correct statement is