Equation of motion in 2D

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Whilst researching for a motion related software issue, I came across the following on Wikipedia

"using 2D vectors, the equation $v^2 = u^2 + 2as$ becomes $v^2 = u^2 + 2a \bullet (r - r_0)$" (Paraphrased)

In summary, $as$ becomes $a \bullet s$

I have searched google, etc and found no references to why this is the case and I can't make sense of it. I can also find no reference to how a scalar can be added to a vector.

My questions...

Is this correct or an error in the wikipedia page?

If correct, then

  1. Why is this the case? - I can't see a reason why multiplication would not work for vectors as it does for scalars
  2. How do I add a vector ($u^2$) to a scalar ($a \bullet \Delta r$)?

Cheers

Rob

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OK I slightly misunderstood the concept of vector multiplication The answer (as alluded to in the comments) is that the equation is correct. $u^2$ is in fact a scalar, the entire equation returning a scalar value. The whole equation makes sense but is actually of zero use to me in my context