I won't show you how to do each but I will help you through the first two.
2 (x + 10) = 2 (3x - 8)
Step 1: Divide both sides by 2 to get: (x + 10) = (3x - 8)
Step 2: Subtract x from both sides to get: 10 = 2x - 8
Step 3: Add 8 to both sides to get: 18 = 2x
Step 4: Divide both sides by 2 to get: x = 9
2 (12 - w) = -2 (w - 17) - 10
Step 1: Distribute the 2 and -2 on both sides to get: 24 - 2w = -2w + 34 -10
Step 2: Simplify to get: 24 - 2w = -2w + 24
Step 3: Add 2w to both sides to get: 24 = 24
Since it ended like that, w = any value
If you need more help, just message me.