Step-by-step explanation:
Let us assume that the cost of per pound of apples  = $ x
Assume that the cost of per pound of potatoes  = $ y
Now, according to question:
The cost of  8 pounds of apples and 5 pounds of potatoes  = $25.50
⇒ Cost of 8 pounds of Apple +  Cost of 5 pounds of potatoes  =  $25.50
⇒ 8 x (Cost of 1 pound apple)  +  5 x ( cost of  1 pound potato )  = $25.50
⇒ 8 x + 5 y =  $25.50  .... (1)
⇒  5 y =  25.5 - 8 x
Similarly,
The cost of 3 pounds of apples and 10 pounds of potatoes = $18.50
⇒ 3 x + 10 y =  $18.50  .... (2)
or, Â 1.5 x +5 y = Â $ 9.25 Â ( dividing the equation by 2) Â
⇒ 5 y =  9.25  - 1.5 x
Now, comparing both equations,we get:
25.5 - 8 x = 9.25 Â - 1.5 x
⇒ 25.5 - 9.25 =  8 x - 1.5 x
⇒ 16.25 =  6.5 x
⇒ x = 2.5
Putting this value of x in  5 y =  9.25  - 1.5 x, we get:
5 y  = 9.25 - 1.5 (2.5)
⇒ 5 y =  5.5
⇒ y = 1.1
So, the cost of 1 pound of apples  = $2.5
The cost pf 1 pound of potatoes = $1.1
The ordered pair (x,y) is given as : (x,y) Â = (2.5,1.1)