cual es el valor de x y y en la siguiente ecuacion: 2x+7y=5 3x+14y=3?
回答 (8)
2019-03-22 9:02 am
2x + 7y = 5 …… [1]
3x + 14y = 3 …… [2]
[1]×3: 6x + 21y = 15 …… [3]
[2]×2: 6x + 28y = 6 …… [4]
[4] - [3]:
(6x + 28y) + (6x - 21)y = -9
7y = -9
y = -9/7
y = -9/7 → [1]:
2x + 7(-9/7) = 5
2x = 14
x = 7
x = 7, y = -9/7
3x + 14y = 3 …… [2]
[1]×3: 6x + 21y = 15 …… [3]
[2]×2: 6x + 28y = 6 …… [4]
[4] - [3]:
(6x + 28y) + (6x - 21)y = -9
7y = -9
y = -9/7
y = -9/7 → [1]:
2x + 7(-9/7) = 5
2x = 14
x = 7
x = 7, y = -9/7
2019-03-22 9:46 am
4x+14y = 10
3x+14y = 3
x = 7
y = -9/7
3x+14y = 3
x = 7
y = -9/7
2019-03-23 10:37 am
What is the value of x and y in the following equation:
2x + 7y = 5
3x + 14y = 3
4x + 14y =10
x = 7, y = -9/7
2x + 7y = 5
3x + 14y = 3
4x + 14y =10
x = 7, y = -9/7
2019-03-23 12:44 am
--
-- 4x -- 14y = - 10
3 x + 14y = 3_________add
-- x = -- 7
x = 7
14 + 7y = 5
7y = -- 9
y = -- 9/7
x = 7 , y = -- 9/7
-- 4x -- 14y = - 10
3 x + 14y = 3_________add
-- x = -- 7
x = 7
14 + 7y = 5
7y = -- 9
y = -- 9/7
x = 7 , y = -- 9/7
2019-03-23 12:11 am
(1) : 2x + 7y = 5 → 7y = - 2x + 5 → 14y = - 4x + 10
(2) : 3x + 14y = 3 → 14y = - 3x + 3
14y = 14y
- 4x + 10 = - 3x + 3
- 4x + 3x = 3 - 10
- x = - 7
→ x = 7
Recall (1) : 2x + 7y = 5
7y = - 2x + 5
7y = - 14 + 5
→ y = - 9/7
(2) : 3x + 14y = 3 → 14y = - 3x + 3
14y = 14y
- 4x + 10 = - 3x + 3
- 4x + 3x = 3 - 10
- x = - 7
→ x = 7
Recall (1) : 2x + 7y = 5
7y = - 2x + 5
7y = - 14 + 5
→ y = - 9/7
2019-03-22 6:41 pm
2x + 7y = 5 ... (1)
3x + 14y = 3 ... (2)
Solving equation (1) and (2)
From equation (2) 3x + 14y = 3
x = (3 - 14 y)/3
above equation substitute in equation (1)
2(3 - 14 y)/3 + 7y = 5
y = -9/14
above value substitute in (1)
2x + 7(-9/14) = 5
2x – 9/2 = 5
x = 19/4
3x + 14y = 3 ... (2)
Solving equation (1) and (2)
From equation (2) 3x + 14y = 3
x = (3 - 14 y)/3
above equation substitute in equation (1)
2(3 - 14 y)/3 + 7y = 5
y = -9/14
above value substitute in (1)
2x + 7(-9/14) = 5
2x – 9/2 = 5
x = 19/4
2019-03-22 9:38 am
What is the value of x and y in the following equation:
2x + 7y = 5
3x + 14y = 3
4x + 14y =10
x = 7. y = -9/7
2x + 7y = 5
3x + 14y = 3
4x + 14y =10
x = 7. y = -9/7
收錄日期: 2021-05-01 22:32:53
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