[tex] \boxed{ \boxed{ \sf{\frac{1}{2} \alpha - ( - \frac{5}{2} ) = - \alpha + 1}} }\\ [/tex]
[tex] \boxed{ \sf{ \frac{1}{2} \alpha \frac{5}{2}} = \alpha + 1} \\ [/tex]
[tex] \boxed{ \sf{ \alpha + 5 = 2\alpha + 2 } }[/tex]
[tex] \boxed{ \sf {\alpha - 2\alpha = 2 - 5}}[/tex]
[tex] \boxed{ \sf{ - \alpha = - 3}}[/tex]
[tex] \large \boxed{ \boxed{ \bold{a = 3}}}[/tex]