- #1
the7joker7
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Homework Statement
Find the area of a triangle `PQR`, where `P=(0,4,4)`, `Q=(2,-6,-5)`, and `R=(-3,-5,6)`
The Attempt at a Solution
The vector PQ = (2, -10, -9)
The vector PR = (-3, -9, 2)
Using matrixes I set up something that looks like this...
I J K
2 -10 -9
-3 -9 2
Then using the matrix methods I get.
I(-20 - 81) - J(4 - 27) + K(-18 - 30)
I(-101) - J(-23) + K(48)
I take the square root of the squares and get.
109.4349122
Answer = 57.0832725061
What's the problem?