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#1 2007-01-20 06:57:28
- RickyOswaldIOW
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- Registered: 2005-11-18
- Posts: 212
Intersection of two lines
Find the points of intersection of the following pair of lines:
2x + 4y = 16
y = 3x - 10
Firstly I get the value of y from the first line
2x + 4y = 16
4y = 16 - 2x
y = 4 - 1/2x
Now I equate the two expressions for y
3x - 10 = 4 - 1/2x
5/2x = 14
5x = 28
x = 28/5
I think this is where I have made the mistake, but I will go on
Now we can use the value of y to find the value of x
y = 3(28/5) - 10
y = 84/5 - 10 = 134/5
Thus the point of intersection is (not) (134/5, 28/5)...
Aloha Nui means Goodbye.
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#2 2007-01-20 07:00:35
- RickyOswaldIOW
- Member
- Registered: 2005-11-18
- Posts: 212
Re: Intersection of two lines
3x - 10 = 4 - 1/2x
7/2x = 14
7x = 28
x = 4!
Thanks anyway 
Aloha Nui means Goodbye.
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