Okay, i tried this a bunch of times but never found out.
simplify the expression:
4(b-6)+19

4(b-6)+19

Easily you would better start with distributing 4 to the brackets

4(b -6) = 4*b    -     4*6 = 4b  -  24

then add 19 to these terms, we get:

4b - 24 + 19

combine like terms (which are -24 + 19), we get:

4b - 5

That's it

Hope that helps