If the equations have the same slope for example y=4x+2 AND y=4x+3 have the smae slope of 4/1, making them parallel but if the don't have the same slope for example y=2x+3 and y=4x+4 then they are not parallel
Contour <span>interval (CI) </span>
The geologic history of the Earth is broken up into hierarchical chunks of time. From largest to smallest, this hierarchy includes eons<span>, eras, periods, epochs, and ages.
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