`bb(b o t)`

`bb(43.)`

`3sqrt18 -3sqrt50 -6sqrt200`

`=3sqrt{3^2 .2}  -3sqrt{5^2 .2} - 6sqrt{10^2 .2}`

`=3.3sqrt2 - 3.5sqrt2 - 6.10sqrt2`

`=9sqrt2 - 15sqrt2 - 60sqrt2`

`=-66sqrt2`

`bb(44.)`

`sqrt45 - 5sqrt5 - 7sqrt80`

`=sqrt{3^2 .5} - 5sqrt5- 7sqrt{4^2 .5}`

`=3sqrt5 - 5sqrt5 - 7.4sqrt5`

`=-2sqrt5 - 28sqrt5`

`=-30sqrt5`

`bb(45.)`

`3sqrt5 +6sqrt20 - 3sqrt80`

`=3sqrt5 + 6sqrt{2^2 . 5} - 3sqrt{4^2 .5}`

`=3sqrt5 + 6 .2sqrt5 - 3.4sqrt5`

`=3sqrt5 + 12sqrt5 - 12sqrt5`

`=3sqrt5`

`bb(46.)`

`2sqrt7 - 5sqrt28 - 7sqrt63`

`=2sqrt7 - 5sqrt{2^2 .7} - 7sqrt{3^2 . 7}`

`=2sqrt7 - 5.2sqrt7 - 7.3sqrt7`

`=2 - 10sqrt7 - 21sqrt7`

`=-29sqrt7`

`bb(47.)`

`5sqrt5 + 20sqrt20 - 75sqrt75`

`=5sqrt5 + 20sqrt{2^2 .5} - 75sqrt{5^2 .3}`

`=5sqrt5 + 20 .2 sqrt5 - 75 . 5sqrt3`

`=5sqrt5 +40sqrt5 - 375 sqrt3`

`=45sqrt5 - 375 sqrt3`

`bb(48.)`

`15sqrt6 + 5sqrt24 - 7sqrt54`

`=15sqrt6 + 5sqrt{2^2 .6} - 7sqrt{3^2 .6}`

`=15sqrt6 + 5.2 sqrt6 - 7.3 sqrt6`

`=15sqrt6 + 10sqrt6 - 21sqrt6`

`=4sqrt6`

`bb(49.)`

`3sqrt6 + 10sqrt150 -6sqrt216`

`=3sqrt6 +10sqrt{5^2 .6 } - 6sqrt{6^2 .6}`

`=3sqrt6 + 10 .5sqrt6 - 6 .6sqrt6`

`=3sqrt6 + 50sqrt6 - 36sqrt6`

`=17sqrt6`

`bb(50.)`

`10sqrt11 - 5sqrt44 - 5sqrt99`

`=10sqrt11 - 5sqrt{2^2 .11} -5sqrt{3^2 .11}`

`=10sqrt11 - 5.2sqrt11- 5.3sqrt11`

`=10sqrt11 - 10sqrt11 - 15sqrt11`

`=-15sqrt11 .`