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Prove that the figure is a parallelogram. If so, classify the parallelogram. Be specific and justify your answer.

What is the perimeter and area? ​

Prove that the figure is a parallelogram. If so, classify the parallelogram. Be specific-example-1
User KevBot
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1 Answer

7 votes

Answer:

Explanation:

If it is a parallelogram the opposite sides will a have the same slope.

Using the diagram we see from the coordinates of A and B:

Slope of AB = (5 - -1)/(-1 - -5)

= 6/4

= 3/2.

In the same way

slope of CD = (2 - -4) / (1 - -3)

= 3/2.

So AB and CD can be shown to be parallel.

Similarly the lines BC and AD are parallel.

So the figure is a parallelogram

Finding the perimeter (counting the units between the points):

Perimeter = 2AB + 2BC

By Pythagoras:

AB = sqrt (6^2 + 4^2) = sqrt 52

BC = sqrt (3^2 + 2^2) = sqrt 13

So Perimeter = 2sqrt52 + 2sqrt13

= 4sqrt13 + 2 sqrt13

= 6sqrt13

or 21.63 unit^2 to 2 decimal places.

Area = sqrt52 * perpendicular distance between the lines AB and CD.

User Pavel Slepiankou
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