which regression is better

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suppose that we have two input vector and the variables in each vectors are independent and uncorrelated from each other,just only there is relationship between two vector,but not itself in each vector's variable,let say

x=rand(1,10);
>> x

x =

  Columns 1 through 9

    0.8147    0.9058    0.1270    0.9134    0.6324    0.0975    0.2785    0.5469    0.9575

  Column 10

    0.9649

y=10.*x+15

y =

  Columns 1 through 9

   23.1472   24.0579   16.2699   24.1338   21.3236   15.9754   17.7850   20.4688   24.5751

  Column 10

   24.6489

that means that variables inside $x$ are uncorrelated,but $y$ and $x$ are correlated,my question is which regression analysis is related to this problem?

plot(x,y)

enter image description here

does it means that linear regression is best?

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On BEST ANSWER

The regression procedure aims to find the most suitable parameters for the following problem: $$ (\alpha_1,\dots,\alpha_n)\ \mbox{s.t.}\ F((x;\alpha_1,\dots,\alpha_n))\approx f(x), $$

where $F(\cdot)$ is the regression function and $f(x)$ is the function that you want to approximate.

Therefore, since you shown a "perfect" linear relation between $x$ and $y$ you may want to use $$ F(x;\alpha,\beta)=\alpha x+\beta. $$

The goodness of fit will be measured by $\rho^2$, coefficient of determination.

Moreover, be aware that even if you'd had a parabolic relation, i.e. $y=ax^2$, you could have used: $$ x^*=x^2, $$ and your relation would have been $$ y=ax^*, $$ so that you could have used a linear regression function again (be aware that error should be coped with differently).