Please help i will mark branliest

Need ! give step by step solutions on how to solve number one [tex]\frac{9-2\sqrt{3} }{12+\sqrt{3} }[/tex] number two [tex]x+4=\sqrt{13x-20}[/tex] number three (domain and range) [tex]f(x)=2\sqrt[3]{x} +1[/tex]

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The sum of the reciprocal of a positive number and the reciprocal of 2 more than the number is 3/4 equation: the number is