Factor pairs of 158 are any two numbers that, when multiplied together, equal 158. The question to ask is “what two numbers multiplied together equal 158?” Every factor can be paired with another factor, and multiplying the two will result in 158.
To find the factor pairs of 158, follow these steps:
Step 1:
Find the smallest prime number that is larger than 1, and is a factor of 158. 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 2.
Step 2:
Divide 158 by the smallest prime factor, in this case, 2:
158 ÷ 2 = 79
2 and 79 will make a new factor pair.
Step 3:
Repeat Steps 1 and 2, using 79 as the new focus. Find the smallest prime factor that isn’t 1, and divide 79 by that number. In this case, 79 is the new smallest prime factor:
79 ÷ 79 = 1
Remember that this new factor pair is only for the factors of 79, not 158. So, to finish the factor pair for 158, you’d multiply 2 and 79 before pairing with 1:
2 x 79 = 158
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 158:
(1, 158), (2, 79)
So, to list all the factors of 158: 1, 2, 79, 158
The negative factors of 158 would be: -1, -2, -79, -158