Step 1 = the opposite of a sum is the sum of its opposites
Step 2= Subtraction as adding the opposite
Step 3=Any order, Any grouping
Step 4= Combine like terms
Step 5= Combine like terms
I would seek other's advice for these --^
All you need to do for the bottom one is multiply.
-4 times 3a
-4 x 3 = -12
-4 times 3a = -12a
-4 times -2b
-4 x -2 = 8
-x- = +
-4 x -2 b = 8b
-4 x 4c
-4 x 4 = -16
-4 x 4c = -16c
