(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Find the area of a triangle `PQR`, where `P=(0,4,4)`, `Q=(2,-6,-5)`, and `R=(-3,-5,6)`

3. 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?

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# Homework Help: Finding Triangle Area using Cross Product

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