The sequence: _ , 4, _ , _ , 10
Okay, I know that this sequence is very easy to determine despite not knowing the values of $d$ and $t_1$ but I chose a very easy sequence because I just wanna know how would one solve for $d$ or $t_1$ without given the other... if that's possible.
I'm just very curious as to if there's a way or not, just in case this is given in a more complex sequence.
Or I may be wrong and they'd never give us something like this when it comes to more harder sequences.
$$\begin{cases} t_1 + d &=& 4 \\ t_1 + 4d &=& 10 \end{cases}$$