Put this into an equation like this:
28 + 5n = x
Now solve for x when n = 4.2.
28 + 5(4.2) = x
Multiply 5 by 4.2 and get
28 + 21 = x
Add 28 and 21 together to get
49 = x
So, the equation showing the phrase and its value when n = 4.2 would be
28 + 5(n) = 49
Hope this helps!