What is the x-intercept of the line with the equation 1/3x+y=-15

Asalesperson earns $320 per week plus 8% of her weekly sales. the expression representing her earnings is 320 + 0.08x. which of the following describes the sales necessary for the salesperson to earn at least $1000 in the one week?

What is the name used to describe a graph where for some value of x, there exists 2 or more different values of y?

Select all the expressions that will include a remainder.