W^2+5w=104

w^2 is w to the second power

Minus 104 from both sides
w²+5w-104=0
ok, factor
what 2 numbers multiply to get -104 and add to get 5?
-8 and 13
(w-8)(w+13)=0
set to zero
w-8=0
w=8

w+13=0
w=-13

w=-13 or 8

1.17+3.99a. you combine the terms with a to create 3.99 and the 1.17 stays because it has no like terms or a variable