Simplify the following expression.
(3x + 5 )2 + ( 3x - 5 )2
Show answer & explanation
Correct answer: D
Explanation
The correct answer is option 4 i.e. 2(9x2 + 25).
(a + b)2 = a2 + b2 + 2ab
(3x + 5 )2 + ( 3x - 5 )2
= 9x2 + 25 + 30x + 9x2 + 25 - 30x
= 2(9x2 + 25)