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**sigma1** the$\displaystyle N^{th}$ term of an A.P is denoted by $\displaystyle U_{n}$ and the sum of the $\displaystyle 1^{st}n$ terms by $\displaystyle S_{N}$ in a certain A.P ;; $\displaystyle U_{5}+U_{16}=44$ and$\displaystyle S_{18}=3S_{10}. $calculate the value of the first term and the common difference.

i have been trying to get two equations from the given equation using the rules for arithmetic progression but i have been unable to do so..

i really need some help coming up with these equations.