When you're subtracting negatives, you're adding them so... Here's a tip:
-9 - (-83)
So..
-9 + (-83) = -92
42.9 is greater because 42.7<42.9
5.78x10^7
If you need an explanation on how then let me know :)
Answer:
15-4x
Step-by-step explanation:
15 fewer is hinting at subtraction and then it states what we are subtracting 15 from which is the product of 4 and some number (4x).