Answer:
x = 435
y = 145
Explanation:
The key to this problem is that x = 3y. So put that into
x + y = 580 Substitute 3y for x
3y + y = 580 Combine like terms
4y = 580 Divide by 4
4y / 4 = 580 / 4 Do the division
y = 145
x + y = 580 Substitute the value for y
x + 145 = 580 Subtract 145 from both sides
x = 580 - 145 Combine
x = 435