2x + 3y - z = -4 x - y = -3
3x – 2y + 3z = 1
I really need help on how to simplify and how to do all the steps. Systems of equations using substitution

Which point is a solution to the inequality shown in this graph (-3,-3)(3,-1)

Me. i can't figure out this question. give an explanation too. .

Sam is a waiter at a local restaurant where he earns wages of $5 per hour sam figures that he also eams about $3 in tips for each person he serves sam works 6 hours on a particular day. if n represents the number of people sam serves that day, which of the following functions could sam use to figure ehis total earings for the do o a. en) = 30 o b. en) = 5n+ 18