Question

помогите, с решением надо))
все номераа)) пж)) кроме а))

Answer 1

$sqrt{6} *7* sqrt{6*9} = sqrt{36} *7* sqrt{9} =6*7*3=126$, ($sqrt{2* 9^{2} } -10 sqrt{2}$)*$sqrt{2}$=$sqrt{2*2} (9-10)=2*(-1)$=-2,$(3* sqrt{2* 7^{2} }- sqrt{2* 8^{2} }): sqrt{2}= sqrt{2}(3*7-8): sqrt{2}=21-8=13$, $4- sqrt{5t}- sqrt{9*80t/16} -12* sqrt{5t*25} /3=4 sqrt{5x} - sqrt{45t} -5*4 sqrt{5t} = 4sqrt{5t} - sqrt{9*5t} -5*4 sqrt{5t} =4 sqrt{5t} -3 sqrt{5t} -20 sqrt{5t} = sqrt{5t} (4-3-20)=-19 sqrt{5t}$