Answer: orthogonal
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Step-by-step explanation:
For any two vectors defined as follows
u = <a,b>
v = <c,d>
the dot product is computed by
u dot v = a*c + b*d
If the dot product of the vectors is 0, then the vectors are orthogonal. Meaning they are perpendicular to one another.
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Let's find the dot product of these two given vectors
u = < 2, -4 >
v = < 6, 3 >
u dot v = 2*6 + (-4)*3
u dot v = 12 - 12
u dot v = 0
Therefore, these two vectors form a right angle and are orthogonal
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Extra info:
If we can show that u = <a, b> and v = <ka, kb> for some real number k, then we have shown that vectors u and v are parallel.