Number patterns and sequences - Tn Term

[JanleyKrueger]

The number sequence is as follows:

3x+5y; 5x; 7x-5y; 9x-10y...

I need to formulate a general term - Tn=T1+d(n-1)
In the above sequence I have no idea what.
I also think this sequence is non linear.
Please help with a solution
Thanks

 

[HallsofIvy]

If it is non- linear then it cannot be written in that form! Taking $$T_1= 3x+ 5y$$, $$T_2=5x$$, $$T_3= 7x-5y$$, and $$T_4= 9x-10y$$, then you want $$T_2= 5x= 3x+ 5y+ d$$ so [tex]d= 2x- 5y[tex]. But then you want <br /> $$T_3= 7x- 5y= 3x+ 5y+ 2d$$ so $$d= (4x- 10y)/2= x- 10y$$. Those are not the same so this sequence cannot be written in that way.[/tex][/tex]