Is the point on the line? Test with vector equation [x,y] = [2,-3] + t[4,7]

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To determine if points are on the line defined by the vector equation [x,y] = [2,-3] + t[4,7], each point must satisfy the equation by solving for the parameter t. The points P(-2,-10), P(6,5), P(10,14), and P(4,0.5) were tested, yielding results of Yes, No, No, and Yes, respectively. The process involves substituting the points into the equation and solving for t, confirming if the equation holds true. Clarification was provided on the distinction between vector r and "r not," with r0 representing the initial point when t equals zero. Understanding these concepts is crucial for verifying point-line relationships in vector equations.
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Determine if each point P is on the line [x,y] = [2,-3] + t[4,7]

a) P(-2,-10)

b) P(6,5)

c) p(10,14)

d) P(4, 0.5)



Answers: Yes, No, No, Yes



We just learned this today and I'm not sure of the difference between vector r and vector "r not" from r = r0 + tm. I'm not sure where to substitute the given points.
 
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Nevermind, I get it now.
We solve for x and y in the original equation using parametric equations, then isolate for t in the x equation. Substitute that into the "t" in the "y" equation and then sub in the points.
 
DespicableMe said:
Determine if each point P is on the line [x,y] = [2,-3] + t[4,7]

a) P(-2,-10)

b) P(6,5)

c) p(10,14)

d) P(4, 0.5)



Answers: Yes, No, No, Yes



We just learned this today and I'm not sure of the difference between vector r and vector "r not" from r = r0 + tm. I'm not sure where to substitute the given points.

For each of your given points, if you can solve for t so that [x,y] = [2,-3] + t[4,7] is a true statement. For example, to verify that the first point, P(-2, -10) is on the line, solve for t:
<-2, -10> = <2, -3> + t<4, 7>.

Solving, this vector equation, I get t = -1, wbich means that (-2, -10) is on the line.

r0 is just some specific vector. In your line equation, r0 corresponds to the point at which t = 0. It's written "r naught" or "r nought".
 
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