For a semicircular region OABCD, a triangle ABD in which AB = 3 cm and BD = 4 cm removed. Find the perimeter of remaining figure.



We have,AB = 3 cm; BD = 4 cmNow, we know that, angle in a semi -circle is a right angle.So, ABD = 90°So, ABD is a right .Now, AD2 = BD2 + AB2AD2 = 42 + 32 = 16 + 9 = 25AD = 5 cmSo, diameter, AD = 5 cmNow, circumference of semicircle OABCDO = π×radius + diameter = 3.14 × 2.5 + 5 =12.85 cm 

Now, when the triangle ABD is removed, then the figure becomes, 



so, circumference of the remaining figure = 7.85 + AB + BD = 7.85 + 3 + 4 = 14.85 cm


 

  • 2
What are you looking for?