Combine like terms to create an equivalent expression.

3.4-2.8d+2.8d-1.3

2.1

Step-by-step explanation:

when you combine like terms you have to combine the d's with the d's and the nonvariable number with the nonvariable number.

this is how it should look like

(-2.8d+2.8d) + (3.4 + (-1.3))

a negitive plus a posative cancel out so the d's disapier and now you only have 3.4+-1.3. this is just like subtracting so you can put it like this

3.4-1.3 and you will get 2.1