SOLUTION: David wants to add one more dot to the diagram below so that the four dots form the four vertices of a parallelogram. If A = (3,4), B = (4,-1), C = (6,8), then where should D be t
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-> SOLUTION: David wants to add one more dot to the diagram below so that the four dots form the four vertices of a parallelogram. If A = (3,4), B = (4,-1), C = (6,8), then where should D be t
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Question 1209346: David wants to add one more dot to the diagram below so that the four dots form the four vertices of a parallelogram. If A = (3,4), B = (4,-1), C = (6,8), then where should D be to form parallelogram ABCD? Answer by math_tutor2020(3816) (Show Source):
To go from B to C we go up 9 and right 2
Start at point A(3,4) and go up 9 and right 2 so you arrive at (5,13)
This is where D should be placed to get parallelogram ABCD.
Technically there are 2 other spots D could go if we didn't care about the order of ABCD. But I'll assume that the order matters.
To prove that ABCD is a parallelogram, you need to show that
slopeAB = slopeCD
slopeBC = slopeAD
I'll let the student do these verifications. The slope formula is
m = (y2-y1)/(x2-x1)
or you can use the rise/run concept.
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