Friday

August 1, 2014

August 1, 2014

Posted by **Anonymous** on Tuesday, December 11, 2012 at 10:18am.

- calculas -
**Steve**, Tuesday, December 11, 2012 at 10:32amget the sides of the triangle, then use Heron's formula:

PQ = √(1^2+2^2+4^2) = √21

QR = √(3^2+0^2+4^2) = 5

RP = √(2^2+2^2+0^2) = √8

I'll let you use Heron's formula. Probably better to convert to decimals rather than having all those nested roots.

- OR - calculus -
**Reiny**, Tuesday, December 11, 2012 at 11:07amarea of triange = (1/2)|vector PQ x vector PR|

vector PQ = [1,2,4] and vector PR = [-2, 2,0}

PQ X PR = [-8,-8,6]

area = (1/2)√(64+64+36) = 1/2 √164

= 1/2 (2√41) = √41

- calculus - duh -
**Steve**, Tuesday, December 11, 2012 at 11:31amgood job, Reiny. Forgot about vectors!

**Related Questions**

Vectors/Calculus - The question asks me to find the area of the triangle with ...

Precalculus - The sides of an isosceles triangle are 10 cm, 10 cm, and 12 cm. A ...

geometry - Theres a circle with an equilateral triangle in the middle. The ...

Math - Two vertices of a right triangle are (0,1) and (0,6). The area of the ...

coordinate geomoetry - PLEASE SEND ME THE ANSWERS TO MY EMAIL ADDRESS Find the ...

math - triangle ABC has vertices A(3,4), B(4,-3) and C(-4,-1). a. draw a sketch ...

geometry - Please use this for the portfolio. You will need graph paper. 1. ...

Physics - How can i find the area of the triangle vertices (2,-3,1), (1,-1,2)&(-...

Matrices - A triangle has vertices (1, 4), (1, 1), and (−3, 1). The ...

calculas - find the perimeter of the rectangle with maximum area that can be ...