Question

ajutor ..
a+ |a+1|=7

Answer 1

$a+|a+1| = 7 \\ \\ |a+1|= 7-a \\ \\ \sqrt{(a+1)^2} = 7-a \Big|^2 \\ \\\Big(\sqrt{(a+1)^2}\Big)^2 = (7-a)^2 \\ \\ (a+1)^2 = (7-a)^2 \\ \\ a^2+2a+1 = 49-14a+a^2 \\ \\ a^2-a^2+2a+14a = 49-1 \\ \\ 16a= 48 \\ \\ a = \dfrac{48}{16} \\ \\ a=3 \\ \\ \Rightarrow \boxed{S = \Big\{3\Big\}}$