In this problem, we must solve some linear equations.
1)
[tex]\begin{gathered} 4\cdot(a+1)=12, \\ a+1=\frac{12}{4}, \\ a+1=3, \\ a=3-1, \\ a=2. \end{gathered}[/tex]2)
[tex]\begin{gathered} 13+2k=5+4k, \\ 13-5+2k=4k, \\ 8+2k=4k, \\ 4k-2k=8 \\ 2k=8, \\ k=\frac{8}{2}, \\ k=4. \end{gathered}[/tex]3)
[tex]\begin{gathered} -4e+28=10e, \\ 28=10e+4e, \\ 28=14e, \\ e=\frac{28}{14}, \\ e=2. \end{gathered}[/tex]4)
[tex]\begin{gathered} -6(4+c)=-66, \\ 4+c=\frac{-66}{-6}, \\ 4+c=11, \\ c=11-4, \\ c=7. \end{gathered}[/tex]Answers
• a = 2
,• k = 4
,• e = 2
,• c = 7