I need help with this.

Solve the equation x/4 - 5= -8 -27 -12 -7 12

Find the domain of the following expression: 1/(√x)-2

21 type the correct answer in the box. use numerals instead of words. if necessary, use / for the fraction bar. the solution set of n2 - 14n = -45 is { (separate the solutions with a comma)