[tex]\begin{gathered} a.\text{Payment}=2000+210x\text{ (where, x is the number of month)} \\ b\text{. Let, put the value of x=1,2,3,4,5(month)} \\ \text{and value of payment you will get.} \\ c.17750=2000+210x \\ 210x=15750 \\ x=75\text{ month} \end{gathered}[/tex]