SSC CPO 2019 PYQ — Question 126

SSC CPO Tier I - 12th March 2019 - Shift 2 • Quantitative Aptitude • Q126

If (2x + 3)3 + (x - 8)3 + (x  13)3 = (2x + 3)(3x - 24)(x + 13), then what is the value of x?

Show answer & explanation

Correct answer: A

Explanation

The correct answer is Option 1 i.e. -2

(2x + 3)3 + (x - 8)3 + (x + 13)3 = (2x + 3)(3x - 24)(x + 13) = 3(2x + 3)(x - 8)(x + 13)

Let,

a = 2x + 3, b = x - 8, c = x + 13

Since, a3 + b3 + c3 = 3abc

So, a + b + c = 0

⇒ 2x + 3 + x - 8 + x + 13 = 0

⇒ 4x = -8

⇒ x = -2