Find the scalar equation of the plane that contains the parallel and distinct lines x=1, (y-3)/4=z/2 and x=5, (y+5)/2=(z-3)/1?
Answer is 7x+2y-4z-13=0
the direction vector of the 1º line is(0,4,4) or (0,1,1) to make it more easy the direction of 2º line is (0,2,1) To find the plane equation containing this 2 lines find the vector product of this 2 vectors, and later make that the plane pass through one of the points of the lines (1,3,0) or (5,-5,3)
@Ruka
Where did you get those direction vectors?
(y-3)/4=z/4 this is line equation in continuous form
got it?
No.
ok. P is point, V direction vector. Line equation: P(a,b,c) + t*V(i,j,k) = (x,y,z)
this is equivalent to 3 equations: x=a+t*i y=b+t*j z=c+t*k solving all of them for t: x-a/i =t y-b/j=t z-c/k=t put them all together: x-a/i=y-b/j=z-c/k like you can see, in the denominators you have the components of the direction vector and in the nominator the points through which the lione goes
got it?
Where did the other 4 come from? For the first one, shouldn't it be (0, 4, 2)? =(0, 2, 1) ?
oh, sry i made a mistake, you right
(0, 4, 2)=(0, 2, 1)
Because the lines are parallel...
you could take perpendicular vector to any of this two (0,-1,2) and find it's vector product with (0,2,1)
or use the points through which this lines goes to find the other vector, which won't be paralel
Huh? How do you get a, b, and c? ax+by+cz+d=0
(5,-5,3) -(1,3,0) =(4,-8,3)
Because the direction vector needs to equal (-7, -2, 4) or (7, 2, -4)
ok. vector product of (0,2,1) x (4,-8,3)= (14,4,-8) plane equation using this point (5,-5,3): 14(x-5)+4(y+5)-8(z-3)=0 14x-70 +4y+20-8z+24=0 14x+4y-8z=70-20-24=26 which is you answer multiplied by 2
(5,-5,3) -(1,3,0) =(4,-8,3)
the 2 points of the lines
ok?
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