Question

n + 4 - 9 - 5n
simplify the equation

Answer 1

The trick is to subtract the numbers containing the variables, in this case the N's, and the ordinary numbers, separately. The way to do it in your case is the following:

n + 4 - 9 - 5n

You first look at the figures containing N's. Oh, look we have positive 1 (n) and -5 (-5n). When adding those together, n + (-5n), what do you get? That's right, (-4n).

Next, you look at the ordinary numbers, the ones not containing any N's, namely positive 4 and negative 9. Now, what is 4 + (-9)? Exactly, (-5).

Lastly, you combine the two, which gives you -4n-5.