Answer :
[tex](n \times (12 + 18)) + 43 = 103[/tex]
[tex]30n + 43 = 103[/tex]
Subtract both sides 43
[tex]30n + 43 - 43 = 103 - 43[/tex]
[tex]30n = 60[/tex]
Divide both sides by 30
[tex] \frac{30n}{30} = \frac{60}{30} \\ [/tex]
[tex]n = 2[/tex]
[tex](n \times (12 + 18)) + 43 = 103[/tex]
[tex]30n + 43 = 103[/tex]
Subtract both sides 43
[tex]30n + 43 - 43 = 103 - 43[/tex]
[tex]30n = 60[/tex]
Divide both sides by 30
[tex] \frac{30n}{30} = \frac{60}{30} \\ [/tex]
[tex]n = 2[/tex]