Question 1180833
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            The numbers in the solution by @mananth are incorrect.


            So I came to bring the correct solution/answer.



<pre>
sides of a triangle are 70cm, 80cm, and 90 cm.


Use the Heron's formula

 
    area = {{{ sqrt(s(s-a)(s-b)(s-c))}}}


s= 1/2 perimeter = (70+80+90)/2 = 120 cm

a, b, c are the sides of triangle


    area = {{{ sqrt(120(120-70)(120-80)(120-90))}}}  cm^2


Area = 2683.28  cm^2


Area = 1/2 base * height


2683.28= (1/2)*80*height


height = 67.08 cm.    <U>the CORRECT ANSWER</U>
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