Calculate the area of the triangle for which two of its sides are given by the vectors `vecA=5hati-3hatj, vecB=4hati+6hatj`.

Explanation

Sides of the triangle `vecA=5hati-3hatj, vecB=4hati+6hatj`
Area of the triangle =, `A=(1)/(2)|vecAxxvecB|`
`|vecAxxvecB|=|(hati,hatj,hatk),(5,-3,0),(4,6,0)|`
`=hati[0-0]_hatj(0-0)+hatk(30+12)=42hatk`
`|vecAxxvecB|=sqrt(0^(2)+0^(2)+42^(2))=sqrt(42)^(2)=42`
`(1)/(2)|vecAxxvecB|=(1)/(2)xx42=21` squared units.