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Line c passes through the points (5, 4) and (9, 16). Line d passes through the points (- 2, 9) and (1, 18) Find the slope of each line and determine whether lines c and d are parallel, perpendicular, or neither. Explain your answer ...

User Dmytro Melnychuk
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1 Answer

28 votes
28 votes

Line C

Point C1 = (x1,y1)= (5,4)

Point C2 = (x2,y2) = (9,16)

Apply the slope (m) formula:


m=(y2-y1)/(x2-x1)

_Replace:


m=(16-4)/(9-5)=(12)/(4)=3

Same process for Line d:

Pont d1= (-2,9) = (x1,y1)

Point d2 = (1,18) = (x2,y2)


m=(18-9)/(1-(-2))=(18-9)/(1+2)=(9)/(3)=3

Both lines have the same slope (3), so, both lines are parallel.

User Tim Randall
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