AP EAMCET2005MathematicsProperties of Triangles
If 3 A A =a , then 3 A A is equal to
Options
- A2 a a+1
- B2 a a-1
- Ca a+1
- Da a-1
Correct answer
B. 2 a a-1
Step-by-step solution
Given that array rlrl & 3 A A & =a & & 3 A- ^3 A A (1-3 ^2 A ) & =a & & 3- ^2 A & =a-3 a ^2 A & & ^2 A(3 a-1) & =a-3 & & A & = a-3 3 a-1 array Now, aligned 3 A A & = 3 A-4 ^3 A A & =3-4 ^2 A=3-4 ( a-3 4(a-1) ) & = 3 a-3-a+3 (a-1) = 2 a (a-1) aligned