in problems with exponents always factorize all the numbers.
In this one you have 10 and 4 which are not factorized so first do so.
10 = 2 * 5 --> 10^n = 2 ^ n * 5 ^n
4 = 2 ^ 2 ----> 4 ^11 = (2^2)^11 = 2^22
now just equal members
5^21 * 2^22 = 2 * 2^n * 5^n
notice that 2 * 2 ^n = 2 ^(n+1)
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mikeCoolBoy
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remember the general theme here: always try to get a COMMON BASE whenever you're dealing with exponentials on both sides.
if you're having difficulty discerning what that common base should be, then it's always a good idea to use primes (as is done in this problem: note that the first step is to break 4 down into 2^2 and to break 10 down into 5*2).
if you're having difficulty discerning what that common base should be, then it's always a good idea to use primes (as is done in this problem: note that the first step is to break 4 down into 2^2 and to break 10 down into 5*2).
Ron has been teaching various standardized tests for 20 years.
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Quand on se sent bien dans un vêtement, tout peut arriver. Un bon vêtement, c'est un passeport pour le bonheur.
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Pueden hacerle preguntas a Ron en castellano
Potete chiedere domande a Ron in italiano
On peut poser des questions à Ron en français
Voit esittää kysymyksiä Ron:lle myös suomeksi
--
Quand on se sent bien dans un vêtement, tout peut arriver. Un bon vêtement, c'est un passeport pour le bonheur.
Yves Saint-Laurent
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Learn more about ron
