You are given two sides of a triangle, a = 4.5 and b = 6, the angle between them is 35 degrees, how do you find the third side and the area of the triangle.?

1 Answer
Aug 1, 2018

Third side is #3.47# unit and area of triangle is #7.74# sq.unit.

Explanation:

Sides #a=4.5 , b=6# and their included angle #/_C = 35^0#

Cosine rule: (for all triangles) #c^2=a^2 + b^2 − 2 a b cos(C) #

#:. c^2=4.5^2 + 6^2 − 2*4.5*6*cos(35)# or

#c^2~~12.02 :. c ~~ 3.47 (2dp)#

Sides #a=4.5 , b=6# and their included angle

#/_C = 35^0#. Area of the triangle is #A_t=(a*b*sin C)/2#

#:.A_t=(4.5*6*sin 35)/2 ~~ 7.74# sq.unit

Area of the triangle is #7.74# sq.unit.

Third side is #3.47# unit and area of triangle is #7.74# sq.unit

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