I agree with what that person told you. The expression -2(x+10) is equivalent to -2x-20
Multiply the outer -2 with the inner x to get -2 times x = -2x
Multiply the outer -2 with the inner term 10 to get -2 times 10 = -20
So overall, -2(x+10) = -2x-20
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So that's how we're able to go from this

to this

The only thing that changes is the left side. The inequality sign will not flip. It only flips if we multiply both sides by a negative number.
The Tenth number percentage
How many red ones were in the bag?
Answer:
D it is d my guy you have fun with that
The percent markup is 62.5%
The work is provided in the image attached.