Help with Math! I need to simplify each expression and show my work!?

(-5.62x-0.8)+(1.12+1.2x)
You don't need the brackets
-5.62x-0.8+1.12+1.2x
Combine 'Like Terms' ie add the x numbers together

0.32 - 4.42x

First, remove the groups, since swapping the groups would still be perfectly fine as it follows the commutative property of addition.

-5.62x - 0.8 + 1.12 + 1.2x

Now, add or subtract like terms, since it can simplify the problem much easier.

Distribute terms with both coefficients and variables (only if you're confused with adding or subtracting which)

(-5.62 + 1.2)x - 0.8 + 1.12

Add the terms outside:

  + 1.12
+ - 0.8
  ----------
   + 0.32

(-5.62 + 1.2)x + 0.32

Then, add the terms inside the group:

  - 5.62
+  1.2
------------
  - 4.42

-4.42x + 0.32

And that's the answer!

(I did this long because you had to show your work. And here it is.)

(Hopefully your school accepts plagiarism) 

(-5.62x - 0.8) + (1.12 + 1.2x)
= -5.62x - 0.8 + 1.12 + 1.2x
= (-5.62x + 1.2x) + (-0.8 + 1.12)
= -4.42x + 0.32

Simply combine 'like' items
0.32 - 4.42x