3x+6y=0
3x+30=y
What is the solutions of the system
Solve by substitution method?
2008-11-26 1:08 pm
回答 (3)
2008-11-26 1:32 pm
✔ 最佳答案
3x + 6y = 0 3x + 30 = y
3x + 6y = 0
3x = -6y
3x + 30 = y
-6y + 30 = y
30 = y + 6y
7y = 30
y = 30/7
3x + 6y = 0
3x + 6(30/7) = 0
3x + 180/7 = 0
3x = -180/7
x = (-180/7)/3
x = (-180/7)(1/3)
x = -60/7
∴ x = -60/7 , y = 30/7
2008-11-26 1:25 pm
Your Question
Equation (1) 3x + 6y = 0
Equation (2) 3x + 30 = y <-- Given
replace y into Equation 1
3x + 6(3x + 30) = 0
3x + 18x + 180 = 0
21x = -180
x = -180/21
replace x into given equation to obtain y
y = 3x + 30
y = 3(-180/21) + 30
y = -540/21 + 30
Answers: x = -8.57, y = 4.29
Equation (1) 3x + 6y = 0
Equation (2) 3x + 30 = y <-- Given
replace y into Equation 1
3x + 6(3x + 30) = 0
3x + 18x + 180 = 0
21x = -180
x = -180/21
replace x into given equation to obtain y
y = 3x + 30
y = 3(-180/21) + 30
y = -540/21 + 30
Answers: x = -8.57, y = 4.29
2008-11-26 1:23 pm
3x+6y=0
3x+30=y
3x = - 6y
-6y + 30 = y
7y = 30
y = 30/7
3x = -180/7
x = - 60/7
3x+30=y
3x = - 6y
-6y + 30 = y
7y = 30
y = 30/7
3x = -180/7
x = - 60/7
收錄日期: 2021-05-01 11:32:21
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