How do you write 18 as a product of prime factors?

3 Answers
Sep 22, 2016

Answer:

#18 = 2xx3xx 3 #

Explanation:

We take 18 and break it down into factors until we reach numbers that are primes.

#18 :rarr 9 and 2#

#18 = 9 xx 2 #

#9# breaks down further into #3 and 3#

#9: rarr 3xx3 #

The prime factors are multiplied together to get a product at the end and together make the answer.

#18 = 2xx3xx3#

Jan 18, 2018

Answer:

See explanation.

Explanation:

To write a prime decomposition of a number #x# you follow this procedure:

  1. Find the lowest prime number #p# which divides #x#. Write #x# as a product: #x=p*x_1#
  2. Repeat this procedure until #x_1# is a prime number.
  3. In the final step you can write the product(s) of repeating prime numbers as a power(s).

Here we have:

#x=18#

It is an even number, so we can write that: #18=2*9#

#9# is a compound number; it is divisible by a prime number #3#:

#18=2*3*3#

Now all the numbers are prime, so the decomposition is complete:

#18=2*3*3#

The product of 2 numbers #3# can be written as a power: #3*3=3^2#, so the final answer can be written as:

#18=2*3^2#

Jan 20, 2018

Answer:

#18=2xx3xx3#

Explanation:

Divide #18# by the prime number #2#.

#18-:color(red)2=9#

Divide #9# by the prime number #3#.

#9-:color(red)3=color(red)3#

This is as far as you can go.

#18=color(red)2xxcolor(red)3xxcolor(red)3#