Factor pairs of 121 are any two numbers that, when multiplied together, equal 121. The question to ask is “what two numbers multiplied together equal 121?” Every factor can be paired with another factor, and multiplying the two will result in 121.
To find the factor pairs of 121, follow these steps:
Step 1:
Find the smallest prime number that is larger than 1, and is a factor of 121. For reference, the first prime numbers to check are 2, 3, 5, 7, 11, and 13. In this case, the smallest factor that’s a prime number larger than 1 is 11.
Step 2:
Divide 121 by the smallest prime factor, in this case, 11:
121 ÷ 11 = 11
11 and 11 will make a new factor pair.
Step 3:
Repeat Steps 1 and 2, using 11 as the new focus. Find the smallest prime factor that isn’t 1, and divide 11 by that number. In this case, 11 is the new smallest prime factor:
11 ÷ 11 = 1
Remember that this new factor pair is only for the factors of 11, not 121. So, to finish the factor pair for 121, you’d multiply 11 and 11 before pairing with 1:
11 x 11 = 121
Step 4:
Repeat this process until there are no longer any prime factors larger than one to divide by. At the end, you should have the full list of factor pairs.
Here are all the factor pairs for 121:
(1, 121), (11, 11)
So, to list all the factors of 121: 1, 11, 121
The negative factors of 121 would be: -1, -11, -121