In this question we have to use the section formula, which is
[tex] P = ( \frac{mx_{2} + nx_{1}}{m+n} , \frac{my_{2} + n y_{1}}{m+n}}) [/tex]
Where m:n is the ratio in which the line is divided by the point P and (x1,y1) and (x2,y2) are the coordinates of the end points .
Here the ratio is
[tex] 2/3 :1/3 = 2:1 [/tex]
Substituting the values , we will get
[tex] x = \frac{2*42+1*-3}{2+1}= \frac{84-3}{3} = \frac{81}{3} = 27 [/tex]
So the x coordinate is x=27
