What is the midpoint of the line segment graphed below

Kelly is a salesperson at a shoe store, where she must sell a pre-set number of pairs of shoes each month. at the end of each work day the number of pairs of shoes that she has left to sell that month is given by the equation s=300-15x , where s is the number of pair of shoes kelly still needs to sell and x is the number of days she has worked that month. what is the meaning of the number 300 in this equation

Simone claims the initial value and y-intercept are the same thing on a graph. is she correct? if you know that a line has a slope of and a y-intercept of 7, what is the equation for that line in slope-intercept form?

The surface area of the triangular prism is .