AP EAMCET201922 Apr 2019Morning ShiftMathematicsProperties of TrianglesActual
If the area of triangle (A B C ) is (b^2-(c-a)^2 ), then ( B= )
Options
- A1
- B( 13 15 )
- C( 1 4 )
- D( 8 15 )
Correct answer
D. ( 8 15 )
Step-by-step solution
Given, ( aligned & Area of a triangle =b^2-(c-a)^2 & =b^2-(c-a)^2 & =(b+c-a)(b-c+a) & =(2 s-2 a)(2 s-2 c) & =4(s-a)(s-c) aligned ) Now ( s(s-a)(s-b)(s-c) =4(s-a)(s-c) ) ( aligned & s(s-b) =4 (s-a)(s-c) & 1 4 = (s-a)(s-c) s(s-b) 1 4 = ( B 2 ) & B= 2 ( B 2 ) 1- ^2 ( B 2 ) = 2 1 4 1- 1 16 = 1 2 15 16 & = 1 2 16 15 = 8 15 aligned )