Answer:9
Step-by-step explanation: x+4=13
x=13-4
x=9
pretty much about the same as before.
a = weight of a large box
b = weight of a small box.
we know their combined weight is 65 lbs, thus a + b = 65.
we also know that the truck has 60 large ones, and 55 small ones, thus 60*a is the total weight for the large ones and 55*b is the total weight for the small ones, and we know that is a total of 3775, 60a + 55b = 3775.

(-1-3i)(-6-i)
=6+i+18i+3i^2
=3i^2+19i+6. Hope it help!
21.6 meters per hour
Solve by dividing 54 by 2.5