Answer:
2a
Explanation:
You want to represent <4, -6> in terms of a = <2, -3>.
Multiple
You recognize that 2×2 = 4 and 2×(-3) = -6. This means the vector <4, -6> can be represented as 2 times a.
<4, -6> = 2a
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Additional comment
You could represent <4, -6> as a+<2, -3>, which we hope you would recognize is a+a = 2a.
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