8/1 + (x-1)/(x+4)
You need the same common denominator (bottom number) to be able to add together so multiply 8 by (x+4) to both bottom and top
8 (x+4)/(x+4) + (x-1)/(x+4)
Add
8 (x+4)+(x-1)/ (x+4)
Distribute the 8 to (x+4)
8x+32+x-1 / x+4
Simplify
9x+31/x+4
:)