Can someone please show a worked solution for the whole of this question?

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1 Answer
Jul 4, 2018

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By cosine formula we know

#cosB=(a^2+c^2-b^2)/(2ac)#

#=>cosB=(11^2+7^2-9^2)/(2*11*7)~~0.5779#

#=>cosB~~54^@42'#

So #sinB~~0.8#

(i) Length of the perpendicular from A to B-C Will be #csinB=7xx0.8=5.6# cm

(ii) Area of the triangle ABC #Delta=1/2xxaxxcsinB#

#=1/2xx11xx5.6=30.8cm^2#