To evaluate the expression $b + 5a$ when $a = 8$ and $b = 6$, follow these steps:

1. Substitute the value of $a = 8$ into the expression.
2. Substitute the value of $b = 6$ into the expression.
3. Perform the multiplication and addition.

Let's do it:

$b + 5a = 6 + 5(8)$

$= 6 + 40$

$= 46$

So, the expression evaluates to 46.

Would you like more details or have any questions?

Here are 5 related questions:

1. What is the value of $b + 5a$ if $a = 3$ and $b = 7$?
2. How does changing the value of $a$ affect the result of the expression $b + 5a$?
3. What happens if both $a$ and $b$ are negative in the expression $b + 5a$?
4. Can you express the formula $b + 5a$ in terms of a different variable by substitution?
5. How would the expression change if instead of adding $b$, you subtracted $b$?

Tip: When substituting values into expressions, always follow the order of operations: parentheses, exponents, multiplication and division (from left to right), and addition and subtraction (from left to right).