Which of the following graphs represent a function?

Which values for a and b will create infinitely many solutions for this system of equations? ax-y=8 2x+y=b

What is the first step of an indirect proof of a number that is divisible by two

Abarbecue sold 26 hamburgers and hot dogs. hamburgers sell for $3.50 each and hot dogs sell for $2.00 each. if the barbecue made $70 in sales, determine and state the number of hot dogs sold.