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Question

16: 2(3 sqrt 2-5 sqrt 2

17: 5 sqrt 2( sqrt 8- sqrt 50)

18: (sqrt 2 - sqrt 3) (sqrt 2 + sqrt 3)

19: (sqrt 5- sqrt 2) (sqrt 5 + sqrt 2)

20: (sqrt 3-2)^2

Answer 1

16) -4*sqrt 2

17) 5*sqrt 2( 2*sqrt 2 - 5*sqrt 2) = -15*sqrt 2

18) sqrt 4 - sqrt 9 = 2-3 = -1

19) sqrt 25 - sqrt 4 = 5-2 = 3

20) 3 - 4*sqrt 3 + 4 = 7 - 4*sqrt3