Question

a+1 supra 1=4 supra a+1

Answer 1

   
$\frac{a+1}{1} = \frac{4}{a+1} \\ \\ (a+1)^2=4 \\ a+1 = \pm \sqrt{4} \\ a+1 = \pm 2 \\ a+1 = 2 \;\;\;=\ \textgreater \ \;\;a_1=2-1=\boxed{1} \\ a+1 = -2 \;\;\;=\ \textgreater \ \;\;a_2=-2-1=\boxed{-3}$