SOLUTION: The vectors are shown as the x and y on top of each other but since I can’t type it out like that, it’ll be separated with commas
The vectors a = (4,2) and b = ( k + 3, k ) are pe
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-> SOLUTION: The vectors are shown as the x and y on top of each other but since I can’t type it out like that, it’ll be separated with commas
The vectors a = (4,2) and b = ( k + 3, k ) are pe
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Question 1112739: The vectors are shown as the x and y on top of each other but since I can’t type it out like that, it’ll be separated with commas
The vectors a = (4,2) and b = ( k + 3, k ) are perpendicular to each other. Find the value of k. Answer by ikleyn(52792) (Show Source):
Thank you for your question.
The condition that two vectors (a,b) and (c,d) in a coordinate plane are perpendicular is
that their scalar product (so called dot-product) a*c + b*d is equal to zero:
a*c + b*d = 0
In your case it means that
4*(k+3) = 2k.
You can easily solve this simple single linear equation
4k + 12 = 2k ====> 2k = - 12 ====> k = -6.
