After john worked at a job for 10 years, his salary doubled. if he started at $x, his salary after 10 years is

$x
$x + 2
$x - 2
$2x

I think its $2x because if a variable is beside a number, it means you multiply.

The expression that would be best fit on the given statement would be 2x. This is because the question says that when John reached 10 years his salary will be doubled. Meaning the x salary will be times to 2, or simply 2x.

When rates are expressed as a quantity of 1, such as 2 feet per second or 5 miles per hour, they are called unit rates. if you have a multiple-unit rate such as 120 students for every 3 buses, and want to find the single-unit rate, write a ratio equal to the multiple-unit rate with 1 as the second term.