Variables represent unknowns. They are often letters (like x) but can also be other symbols like Greek numerics.
Hope this helps!!
8y + x + 12
other then that, you cannot further simplify this, nor can you factor because the greatest common factor for all of them is just 1
13 is a whole number, integer, natural number and rational number. Rational number because it can be written as a fraction like 13/1. It is a whole number because it doesn't have any decimals. It is an integer because an integer is a positive or negative whole number and it is a natural number because a natural number is any positive number greater than 0.
In 4 hours if you count the miles by the road linking the 2 buses. This is because 55 for one bus and 45 for the other bus added together equals 100 miles/hour. Therefore, 4 hours will be the time the 2 buses are 400 miles apart.
