Final answer:
To simplify the expression -2.4x+3.8x-x, combine the like terms together to get 0.4x.
Step-by-step explanation:
To simplify the expression -2.4x+3.8x-x, we can combine the like terms together. Like terms are terms with the same variable and exponent. In this case, all the terms have the variable x with an exponent of 1, so we can combine them.
-2.4x+3.8x-x = (-2.4 + 3.8 - 1)x = 0.4x