Question

find the value of y for the given value of x
y=x+1, x=8

Answer 1

find the value of y for the given value of x
y=x+1 eq. i
x=8 eq. ii
so simple:
put the value of eq ii in eq. i
we get:
y=8+1
y=9

Answer 2

if x=8 then y=(8)+1

therefore, y=9. this is a more simple way of explaining it @uniquejamaica .
Does this make sense to you?