Answer:
(4, 26)
Explanation:
As equations, these statements work out to:
4x + 15y = 400
20x - 4y = -20
First, multiply the first equation by -5, obtaining -20x - 75y = -2000.
Next, add this result to the second equation:
20x - 4y = -20
-20x - 75y = -2000
----------------------------
-79y = -2020. Dividing both sides by -79, we get: y = 25.57.
Subbing 25.57 for y in the first equation, we get 4x + 15(25.57) = 400. Solve this for x:
4x + 383.54 = 400
Solving for x, 4x = 16.46, or x = 4.11.
The solution is approximately (4.12, 25.57), or, when rounded off,
(4, 26).