To solve the equation 45 + 4y = 5, you’ll want to isolate the variable y. Here are the steps:

1. Subtract 45 from both sides of the equation:
   45 + 4y – 45 = 5 – 45
   This simplifies to:
   4y = -40
2. Now, divide both sides by 4 to isolate y:
   4y / 4 = -40 / 4
   This simplifies to:
   y = -10

So, the solution to the equation 45 + 4y = 5 is y = -10.