Archive
28th of March 2017
Mathematics
Q:


  1. 9tobepower x + 2 = 240+9 tobepower x

Kamal Roy - CBSE - Class VI

Tuesday, March 28, 2017 at 18:27:PM

A:

Given 9x+2 = 240 + 9x
⇒ 9x ×  9= 240 + 9x  
Let 9x  = a
⇒ 81a = 240 + a
⇒ 80a = 240
⇒ a = 3
but 9x  = a
⇒  9x  = 3
⇒ 32x  = 3
bases are equal powers should be equated.
⇒ 2x = 1
⇒ x = 1/2

Tuesday, March 28, 2017 at 18:45:PM