2 400 + 20X = 20Y

300 + y = 125x

120 + x = y

300 + y - 125x = 0

120 - y + x = 0

Added the above two types:

420 - 124x = 0

124x = 420

x = 420/ 124 ≈ 3.39

Substituting 120+x = y, we get:

y ≈ 123.39，2，200 + 4Y = 500X ( 1)

400 + 20X = 20Y (2)

By (1)

1000 + 20Y = 2500X (3)

(2)+(3), get

2480X = 1400

62X = 35

X ≈ 0.5645

Y is about 20.56

Please check it and you will know right or wrong. 2, from the first equation,

4Y=500X-200

Y= 125X-50

Substituting Y= 125X-50 into the second equation, there are

400 + 20X = 20( 125X-50)

20+X= 125X-50

X- 125X=-50-20

...，2， 1 200 + 4Y = 500X ①

2 400 + 20X = 20Y ②

Simplify, ① divide both sides of the formula by 4 at the same time to get 300+Y= 125X ③.

② Divide both sides of the formula by 20 to get120+x = y 4.

Substituting ③ into ④ gives 300+ 120+X= 125X.

420= 124X

0, mathematics, unknown quantity, algebraic distribution method, problem solving process,

1 200 + 4Y = 500X

2 400 + 20X = 20Y

Solution: X ≈ 3.39, Y ≈ 123.39.

Problem solving process.