Jawabanmu

2014-08-20T21:52:43+07:00
5√45 - √20 + 12√5 - √45
= 5√9.√5 - √4.√5 + 12√5 - √9.√5
= 5.3√5 - 2√5 + 12√5 - 3√5
= 15√5 - 2√5 + 12√5 - 3√5
= 22√5
2 5 2
2014-08-20T21:53:28+07:00
5√9x5 - √4x5 +12√5-√4x5
=5x3√5 - 2√5 +12√5 -2√5
=15√5-2√5+12√5-2√5
=23√5