Math, asked by riyanimFaip2a, 1 year ago

Find the ratio in which the straight line joining the points (2,-3,5) and (7,1,3) is divided by the xy plane.

Answers

Answered by kvnmurty
0
A(2,-3,5)         B(7,1,3)       

Line AB meets x-y plane at P(x,y, 0).  Both points A & B are on one side of the x-y plane as z coordinates are both positive.

AP : BP = (z coordinate of A - z coordinate of P) / (z coordinate of B - z coordinate of P)
              = (5 - 0) / (3 - 0) = 5 : 3

=====
we can also find the coordinates of P and then find AP, BP too.
 
equation of AB :  x = 2 + 5 t
                            y = -3 + 4 t
                            z = 5 - 2 t
         z is 0 for t = 2.5.  Hence
     P = (14.5, 7, 0).

So  AP = √(12.5²+10²+5²) = 15√5 /2
      BP = √(7.5²+ 6² + 3²) = 9√5 /2

AP : BP =  5 : 3


kvnmurty: click on the red hearts thanks button above pls
Similar questions