Respuesta :
The incorrect step where Kelcy did mistake is given by: Option A: She added ⟨–4, 3⟩ and ⟨5, 1⟩ incorrectly.
How to add two vectors?
Suppose that two vectors are given as:
[tex]x = \: < a,b > \\y= \: < c,d >[/tex]
Then, their addition is given as:
[tex]x + y = \: < a +c , b + d >[/tex]
For this case, we can see that when Kelcy added <-4,3 > and <5,1>, she didn't add -4 and 5 correctly, as it results in +1, and not -1,
Thus, <-4,3> + <5,1> = <1,4>
Thus, wrong addition caused error in the solution.
Thus, the incorrect step where Kelcy did mistake is given by: Option A: She added ⟨–4, 3⟩ and ⟨5, 1⟩ incorrectly.
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