Leroy road six rides at the state fair of texas for $19.56 find constant of the proportionality

Which of these tables represents a non-linear function?

For what values of the variable x is the expression square root of 7x+14+ square root of 7-x a real number?

Which number is located at point a on the number line? a number line is shown from negative 10 to 10 with each interval mark on the number line representing one unit. point a is labeled one interval mark to the right of negative 5.