2x+2y=38 solve with subistution

You call the pizza store and find out that eachpizza has 12 slices. you expect 16 people tocome, and you estimate each person will eat 3slices. how many pizzas should you order

Which of the following is a function? a.) {(-2, -4/5), (-1,-,,-1)} b.) {(-2,,1/,3/,1)} c.) {(-22)} d.) {(-21)}

Determine which expressions represent real numbers and which expressions represent complex number. asaaap! plis!