Can i get a step by step for this?

To which sets of numbers does -12 belong? choose all answers that are correct. a) natural numbers b) integers c) real numbers d) irrational numbers

The suare root of 9x plus 7 plus the square rot of 2x equall to 7

What would be the reasons for lines 3 and 4? a. addition property; subtraction property b. addition property; solve c. substitution property; subtraction property d. substitution property; prove