if 5^|3x+4| = 25^4x , find x ? this is logarithms powerplay ques. I don't understand why is negative 4/11 wrong answer and only positive 4/5 is correct ?

By the way if u put -(4/11) the equation is not satisfied.. the only solution for it is 4/5.

hey Ramkumar, sorry for the mistake I made while posting. The 3x+4 is in modulus function. Now do tell why is -4/11 wrong ?

Hi Amit, |3x+4| = 8x

|3x+4| = 3x+4 if x >= -4/3, in this case the solution is x = 4/5

|3x+4| = -3x-4 if x < -4/3, in this case, -3x-4 = 8x => x = -4/11. But, -4/11 > -4/3. So, this value cannot be taken.

The only solution is x = 4/5

Thank you very much Pv Aaditya !

hi Aditya, one doubt regarding when x>=-4/3 then there is a chance than 8x be also negative. So in that that case 3x+4= -8x => x= -4/11 and if u substitute -4/11 is satisfies the equation also. Please explain if its otherwise