To determine which of the given pairs are factor pairs of $26$, we need to check if the product of each pair equals $26$.

• Choice A: $1 \times 26 = 26$. This is a factor pair of 26.
• Choice B: $2 \times 13 = 26$. This is a factor pair of 26.
• Choice C: $3 \times 12 = 36$. This is not a factor pair of 26.
• Choice D: $4 \times 6 = 24$. This is not a factor pair of 26.
• Choice E: $5 \times 5 = 25$. This is not a factor pair of 26.

The correct factor pairs of $26$ are:

• Choice A: $1$ and $26$
• Choice B: $2$ and $13$

Do you want more details or have any questions?

Here are 8 related questions you might consider:

1. What are the factors of 26?
2. How can you find the factors of a number?
3. What are prime numbers, and is 26 a prime number?
4. What are factor pairs of 30?
5. How do you determine if a number is divisible by another number?
6. What is the prime factorization of 26?
7. Can a number have more than one factor pair?
8. How does understanding factor pairs help in solving quadratic equations?

Tip: When looking for factor pairs of a number, remember that the product of the two factors must equal the original number.