how would I solve:
i know what the answer is, but i don't know how to solve it. please explain how you get the answer. thanx
2x + 7y = 9
y = (4x - 1) / 3
Maths question help!!!! simultaneous equation?
2009-04-26 9:10 am
回答 (4)
2009-04-26 9:27 am
✔ 最佳答案
2x + 7y = 9 equation1y = (4x - 1) / 3 equation 2
plug in equation 2 to equation 1
2x+7(4x-1)=9 lcd:3
.......---------
..........3
6x+28x-7=27
34x-7=27
34x=27+7
34x=34
x=1 answer//
plug in x=1 to equation 1
2(1)+7y=9
2+7y=9
7y=9-2
7y=7
y=1 answer//
2009-04-26 4:29 pm
2x + 7y = 9 (solve by using substitution)
y = (4x - 1)/3
2x + 7y = 9
2x + 7[(4x - 1)/3] = 9
2x + (28x - 7)/3 = 9
3[2x + (28x - 7)/3] = 3[9]
6x + 28x - 7 = 27
34x = 27 + 7
x = 34/34
x = 1
y = (4x - 1)/3
y = [4(1) - 1]/3
y = (4 - 1)/3
y = 5/3
â´ x = 1 , y = 5/3
y = (4x - 1)/3
2x + 7y = 9
2x + 7[(4x - 1)/3] = 9
2x + (28x - 7)/3 = 9
3[2x + (28x - 7)/3] = 3[9]
6x + 28x - 7 = 27
34x = 27 + 7
x = 34/34
x = 1
y = (4x - 1)/3
y = [4(1) - 1]/3
y = (4 - 1)/3
y = 5/3
â´ x = 1 , y = 5/3
2009-04-26 4:24 pm
2x+7y=9
rearranging
y=(9-2x)/7
y=(9-2x)/7= (4x - 1) / 3
cross multiplying
3(9-2x)=7(4x-1)
27-6x=28x-7
34x=34
x=1
sub x=1 ------>y=[4(1) -1)] /3
y=1
hope this helps
rearranging
y=(9-2x)/7
y=(9-2x)/7= (4x - 1) / 3
cross multiplying
3(9-2x)=7(4x-1)
27-6x=28x-7
34x=34
x=1
sub x=1 ------>y=[4(1) -1)] /3
y=1
hope this helps
2009-04-26 4:23 pm
by simultaneous equation....
lets 2x+7y=9 -------1
y=(4x-1)/3------------2
1-2
2x+7(4x-1)/3=9
lets 2x+7y=9 -------1
y=(4x-1)/3------------2
1-2
2x+7(4x-1)/3=9
收錄日期: 2021-05-01 12:19:35
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