Solving linear equations with exactly one solution

baki
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1.Determine the value(s) of k for which the system of linear equations
x + 2y = 1
(k2)x - 2ky = 2
has exactly one solution 3.How do i solve this, i tried the 2x2 matrix
whereby, i had
|1 2|
|k2 -2k|
and tried to make [2 and k^2 = zero] and [-2k = one]
But I can't seem to solve it completely
is there another way we can do this?
 
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baki said:
[ b]1.Determine the value(s) of k for which the system of linear equations
x + 2y = 1
(k2)x - 2ky = 2
has exactly one solution [/b]

[ b]3.How do i solve this, i tried the 2x2 matrix
whereby, i had
|1 2|
|k2 -2k|
and tried to make [2 and k^2 = zero] and [-2k = one]
But I can't seem to solve it completely
is there another way we can do this?
[/b]
Try solving the system, as it is, for x & y.

See how k is involved in that solution.
 
I've tried that and there are 2 values of k, but don't you think when it says it has exactly one solution than it means k should have one value.
 
baki said:
I've tried that and there are 2 values of k, but don't you think when it says it has exactly one solution than it means k should have one value.
No.

It means, "What value or values may k have so that the system has one (x, y) solution?"
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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