How do you do prime factorisation for 48/72?

48:
48/2 = 24 24/2 = 12 12/2 = 6 6/2 = 3
 We can not divide by 2, but we can divide by 3: 3/3 = 1
  That's as far as we go. So I divided by 2 four times and once by 3: Therefore: 48 = 2 * 2 * 2 * 2 * 3
 Now we take 72
 72 / 2 = 36 36 / 2 = 18 18 / 2 = 9 Nine is not divisible by 2, but it is by 3, so: 9 / 3 = 3 3 / 3 = 1
 That's as far as we can go. I divided by 2 three times and by 3 two times. Therefore 72 = 2 * 2 * 2 * 3 * 3 So, taking the bigger picture:
4872=2∗2∗2∗2∗32∗2∗2∗3∗3 Now three two's cancel out and one three cancels out and we get 2\3
answer=2\3

To prime factorise a number, you have to do the prime factor tree..

48 = 2x2x2x2x3
72 = 2x2x2x3x3

6x - 18

Step-by-step explanation:

(2x - 6) + 4(x - 3) =

= (2x - 6) + 4x - 12 =

= 2x - 6 + 4x - 12 =

= 2x + 4 - 6 - 12 =

= (2x + 4x) + (-6 - 12) =

= 6x - 18