What does 'a solution' mean in the context of vector equations?

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Homework Statement



Printed exam question: Solving the equation a × x = b for vectors a, b in R^3. (a) Show that if a × x = b then a · b = 0. (b) Use Q4 above to show that -(a × b)/|a|^2 is a solution of a × x = b.


the question i have is about part b).

by 'a solution' does it mean what x equals?

as in show that x = -(a x b)/|a|^2 is a solution?
 
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Well for part A if b is the cross product of a and x, then b is perpendicular to a and x, which would mean that its angle with a is 90. Since the dot product of a and b is equivalent to |a||b|cos([tex]\vartheta[/tex]), and since cos(90) = 0: the dot product must be 0.

Yes, I think for part B it's saying that that expression is the value of X.