Solve for x
(1.) 5/10x-9=8
(2.) 3/4x-3=1+5/12x

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

Solve the equation for x.3(6x - 1) = 12 i've tried doing the math and i can't find out what i'm doing wrong

Monitors manufactured by tsi electronics have life spans that have a normal distribution with a standard deviation of 1800 hours and a mean life span of 20,000 hours. if a monitor is selected at random, find the probability that the life span of the monitor will be more than 17,659 hours. round your answer to four decimal places.