Hello!
[tex]-1-4s=8[/tex]
[tex]-1-4s+1=8+1[/tex]
[tex]-4s=9[/tex]
[tex]\frac{-4s}{-4}=\frac{9}{-4}[/tex]
[tex]s=-\frac{9}{4}[/tex]
Explanation: This question is super easy for me. First you had to do add 1 from both sides. It gave us -1-4s+1=8+1, then simplify, and it gave us -4s=9. You can also divide by -4 from both sides. It gave us -4s/-4=9/-4, and simplify. And the answer it gave us is s=-9/4 is the right answer. Hope this helps! And thank you for posting your question at here on Brainly. And have a great day. -Charlie