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First, calculate the dot products $y \cdot u = 20$ and $u \cdot u = 5$. The scalar coefficient is $20/5 = 4$.

Conditions: $y = (7,6)$; $u = (2,1)$

First, calculate the dot products $y \cdot u = 20$ and $u \cdot u = 5$. The scalar coefficient is $20/5 = 4$.

Conditions: $y = (7,6)$; $u = (2,1)$