On monday joe bought 10 cups of coffee and 5 donuts for his office at the cost of 1650 it turns out the donuts were much more popular than the coffee on tuesday he bought 5 cups of coffee and 10 donuts for a total of 1425 how much were each cup of coffee

X=coffee

Y= be donuts

Now create two equations to solve

10x+5y= 16.50

5x+10y= 14.25

Now multiply first equation by -2. To solve both equations

-2(10x+5y=16.50)

-20x-10y=-33

Now add the second equation to solve for x

-20x-10y=-33

5x+10y= 14.25

-5x. = -18.75

Now divide -5 both sides

X= -18.75/-5

X=1.25

Coffee cost $1.25 per cup

the graph on the bottom right