Question

em uma P.A. de razao -3 e o 5° termo vale 26. qual e o 2º termo?​

Answer 1

$\large\boxed{\begin{array}{l}\underline{\rm Termo\,geral\,da\,PA}\\\underline{\rm em\,func_{\!\!,}\tilde ao\,de\,um\,termo\,p\,qualquer}\\\sf a_n=a_p+(n-p)\cdot r\\\tt dados\begin{cases}\sf r=-3\\\sf a_5=26\\\sf a_2=?\end{cases}\\\sf a_5=a_2+3r\\\sf 26=a_2+3\cdot(-3)\\\sf a_2-9=26\\\sf a_2=26+9\\\sf a_2=35\end{array}}$