Solving problems with vectors is WAY easier than you think 

In this lesson" Solving problems with vectors is WAY easier than you think " you have a Cartesian equation of a first line and a pint A you need to have the Cartesian equation to another line parallel to first line and pass by A ... our solution is to use the scalar product and the normal vector...
00:13 presentation of the content " Solving problems with vectors is WAY easier than you think "
00:38 how we can use the definition of normal , direction vector and scalar product
00:42 the solution and explanation the link is in the first comment
#Normal_vector_Direction_vector_Cartesian_equation_How_to_solve_problem#math_mastery
property of equality, zero property, trigonometry, algebra, test
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