What is the prime factorization of 245?
a) 5 × 49
b) 7 × 35
c) 5 × 72
d) 52 × 9

To find the prime factorization of a number, divide it by the first number it can be divided by evenly. (Besides 1)

245/2? Nope
245/3? Nope
245/4? Nope
245/5? Yep!!

5 is the first number in the prime factorization of 245

245/5 = 49

49/2? Nope
49/3? Nope
49/4? Nope
49/5? Nope
49/6? Nope
49/7? Yep!!

7 is the second number in the prime factorization of 245

49/7 = 7

Since seven is a prime number it can only be divided by 1 and itself, so the third number in the prime factorization of 245 is 7. :)

The answer is 5 · 7 · 7, but since that's not one of the choices, the answer is 5 · 49 (Because 7 · 7 = 49)

The answer is A :)

Hopefully this helps! If you have any more questions or don't understand, feel free to DM me and I'll get back to you asap :)