Resposta :
Olá!
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[tex]{ \large \displaystyle \sf {a) \: x - 17 = 8}}[/tex]
[tex]{ \large \displaystyle \sf {x = 8 + 17}}[/tex]
[tex]{ \large \displaystyle \sf {x = 25}}[/tex]
[tex] \boxed{ \boxed{ \red{{ \large \displaystyle \sf {S = \left \{ 25 \right \}}}}}} \\ \\ \\ [/tex]
[tex]{ \large \displaystyle \sf {b) \: 6x + 10 = 3x - 5}}[/tex]
[tex]{ \large \displaystyle \sf {6x - 3x = - 5 - 10}}[/tex]
[tex]{ \large \displaystyle \sf { 3x = - 15}} \\ [/tex]
[tex]{ \large \displaystyle \sf { x = \frac{ - 15}{3} }} \\ [/tex]
[tex]{ \large \displaystyle \sf {x = - 5}}[/tex]
[tex] \boxed{ \boxed{ \red{{ \large \displaystyle \sf {S = \left \{ - 5 \right \}}}}}} \\ [/tex]