Simultaneous equation: 2x+3y=8 7x+2y=12?
回答 (7)
2016-11-03 10:55 pm
Multiply the first given equation by 2 and the second given equation by 3:
4x + 6y = 16
21x + 6y = 36
Subtract the first equation here from the second:
17x = 20
x = 20/17
Substitute this value for x in to 7x+2y=12 (or the first given equation) and solve for y:
7 (20/17) + 2y = 12
140/17 + 2y + 12
140 + 34y + 204
34y = 64
y = 64/34 = 32/17
So the solution is x = 20/17, y = 32/17
4x + 6y = 16
21x + 6y = 36
Subtract the first equation here from the second:
17x = 20
x = 20/17
Substitute this value for x in to 7x+2y=12 (or the first given equation) and solve for y:
7 (20/17) + 2y = 12
140/17 + 2y + 12
140 + 34y + 204
34y = 64
y = 64/34 = 32/17
So the solution is x = 20/17, y = 32/17
2016-11-06 7:13 am
2x + 3y = 8
7x + 2y = 12
4x + 6y = 16
21x + 6y = 36
17x = 20
x = 20/17
y = 32/17
7x + 2y = 12
4x + 6y = 16
21x + 6y = 36
17x = 20
x = 20/17
y = 32/17
2016-11-04 9:52 am
2x + 3y = 8, 7x + 2y = 12
7(2x + 3y = 8)
2(7x + 2y = 12)
14x + 21y = 5
14x + 4y = 24
17y = 32
y = 32/17
2x + 3y = 8
2x +3(32/17) = 8
2x = 8 – 3(32/17)
2x = 8(17) – 3(32)/17
x = 8(17) – 3(32)/2(17)
x = 4(17 – 3(4))/17
x = 4(17 - 12)/17
x = 4(5)/17
x = 20/17
7(2x + 3y = 8)
2(7x + 2y = 12)
14x + 21y = 5
14x + 4y = 24
17y = 32
y = 32/17
2x + 3y = 8
2x +3(32/17) = 8
2x = 8 – 3(32/17)
2x = 8(17) – 3(32)/17
x = 8(17) – 3(32)/2(17)
x = 4(17 – 3(4))/17
x = 4(17 - 12)/17
x = 4(5)/17
x = 20/17
2016-11-03 10:57 pm
2x + 3y = 8 ............(1)
7x + 2y = 12 ............(2)
Multiply (1) by 2 and (2) by 3
4x + 6y = 16 ...........(3)
21x + 6y = 36 .........(4)
Subtract (4) from (3)
- 17x = - 20
x = 20/17
Put in (1)
2(20/17) + 3y = 8
3y = 8 - 40/17
= 96/17
y = 32/17
7x + 2y = 12 ............(2)
Multiply (1) by 2 and (2) by 3
4x + 6y = 16 ...........(3)
21x + 6y = 36 .........(4)
Subtract (4) from (3)
- 17x = - 20
x = 20/17
Put in (1)
2(20/17) + 3y = 8
3y = 8 - 40/17
= 96/17
y = 32/17
2016-11-03 10:53 pm
x = 20\/17 and y = 32\/17
2016-11-03 10:52 pm
Bbb
2016-11-03 10:52 pm
x= -3y+8/2
x= -2y+12/7
x= -2y+12/7
收錄日期: 2021-04-21 23:52:15
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