Using the x and y intercepts from the graph to find the slope of the line:
slope = (0 - 2) / (4 - 0)
slope = -1/2
Using the point-slope form:
y - 0 = -1/2 (x - 4)
-2y = x - 4
4 = x + 2y
Coefficient of x is 1 and coefficient of y is 2.
C because eof plus fob will end up being 180
79.8 is the discount of the price of an armchair that originally cost $266.00......... because 266.00÷30%=79.8