Answer :

[tex]3d-2d=-17-8[/tex]  | Like terms on each side

[tex]d=-25[/tex]  | simplify 
apologiabiology
it's important do do the same thing to both sides so the equation will stay equal
exg
3=3
multipy 4
12=12
still true


so 3d+8=2d-17
2d means 2 times d or d+d

so
3d+8=2d-17
subtract 2d from both sides
3d-2d+8=2d-2d-17
d+8=-17
subtract 8 from both sies
d=-25


d=-25