Note that, the coordinates centre of pencil of line is solution of the system of equations 3*x+4*y-10=0 and 3*x-y-5=0.
We have [[x = 2, y = 1]]
Now, put Delta is the line passing the point A(2, 1) and having the slope k. The equation of the line Delta has the form y=k*(x-2)+1.
And then, you find the distance from the center T to the line Delta.
You can try
for i to 2 do subs(sol[i],Equation(Delta)) end do;
Equation of two lines are - x/2 + y = 0 and 2 x + y - 5 = 0.