Weegy: ok this is what u do... it is kinda easy once you get the hang of it.
1. on a calculater u would do
.5 x 3 x 7 x 5 , .5 x 4 x 9 x 7 , and .5 x 2 x 4 x 9
if you write it out you would do the same thing
the fomula for an area of a [ triange is 1/2 times witdh times hieght for a flat triange it is 1/2 times lengh times witdh http:// /question/?qid=20080425131942AA72LVo ]
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