Manipal MET2014MathematicsProperties of Triangles
In a triangle, the lengths of two larger sides are 10 cm and 9 cr. . If the angles of the triangle are in AP , then the length of the third side is
Options
- A5 - 6
- B5 - 6
- C5 6
- D5 6
Correct answer
D. 5 6
Step-by-step solution
Let in the figure, A B C Angles are in A.P. array ll & C= -d, B= and & A= +d array As A+ B+ C=180^ array rrrl & +d+ + -d & =180^ & 3 & =180^ & & & =60^ array Now in A B C , aligned B & = a^2+c^2-b^2 2 a c 60^ & = (10)^2+x^2-9^2 2 10 x 1 2 & = 100+x^2-9^2 20 x x^2-10 x+19 & =0 x & = 10 100-76 2 & = 10 24 2 =5 6 aligned