Ineed on a mathematics question. i need an explanation. solve 2 log x = log 64. x = 8 x = ±8 x = 32 x = 128 why is it not b and rather a? i agree with 8, but i also think that -8 works.

Start by dividing both sides by 2 to get .  Doing the math on the right, keeping in mind that logs have an unwritten base of 10, gives us .  Rewriting this in exponential form is .  That means that x = 8.  Not negative, only positive.

First step is to get rid of the square root. remember that a square root is the same as raising to the (1/2) power. see below: multiply exponents per exponent rules to get: remember you subtract exponents from the denominator and add exponents in the numerator so: simplify further: so a is the correct choice. if you don't understand this google exponent rules and it will you understand. look at the image results.