When the coffee price increases then the amount of sales decreases.
Graph :
Graph the amount of the coffee sales as the function of the coffee price :
axis : Amount of coffee sales.
axis : Coffee price.
Graph of the coffee sales :
![\"\"](\"/userfiles/image/steps_images/step1.JPG\")
![\"\"](\"/test/fckeditor/editor/plugins/fckeditor_wiris/integration/showimage.php?formula=0116acca3e41c7c250440fce3e42e609.png\")
axis : Amount of coffee sales.![\"\"](\"/test/fckeditor/editor/plugins/fckeditor_wiris/integration/showimage.php?formula=125b232ef6e98acd107d00dec780ae3f.png\")
axis : Coffee price.![\"\"](\"/userfiles/50-20-19.gif\")
![\"\"](\"/userfiles/image/steps_images/solution.JPG\")