Question 192370
1.How do we write the equation of a horizontal line? What would be an example?
y = k, where k is any real number, is the equation of a horizontal line.
Ex: y = 10 is a line thru all points where y = 10
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2.How do we write the equation of a vertical line? What would be an example? 
x = k, where k is any real number, is the equation of a vertical line.
Ex: x = 10 is a line thru all points where x = 10.
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Xheers,
Stan H.