Can someone tell me an EASY and understandable way to find the domain of a function PLEASE!!!

When using the linear combination metho e linear combination method to solve a system of linear equations, the four options are:

Yuto and hila attempted to solve the same inequality. their work is shown below. which statement is true about the work shown above? yuto is correct because he isolated the variable correctly and reversed the inequality symbol. yuto is incorrect because he should not have reversed the inequality symbol. hila is correct because she isolated the variable correctly and reversed the inequality symbol. hila is incorrect because she should not have reversed the inequality symbol.

You have 138.72 in your saving account u take out 45.23 and 18.00 you deposit 75.85 into your account