Answer: 22 units
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Step-by-step explanation:
You can use the distance formula

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A shorter method is to subtract the y coordinates and apply absolute value
So either |-4-18| = |-22| = 22
Or, |18 - (-4)| = |18+4| = |22| = 22
This method only works because the x coordinates are the same. We can also use this method if the y coordinates were the same with the x coordinates being different.