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Point C(3.6, -0.4) divides in the ratio 3 : 2. If the coordinates of A are (-6, 5), the coordinates of point B are . 
A (5,-4)
B (5,-2)
C (10,-4)
D (10,-2)

 

If point D divides in the ratio 4 : 5, the coordinates of point D are .
A (62/9,-4)
B (58/9,-4)

 May 10, 2019
edited by AceOfMath  May 10, 2019
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Point C(3.6, -0.4) divides in the ratio 3 : 2. If the coordinates of A are (-6, 5), the coordinates of point B are . 

 

I'm assuming that  C divides  AB  in the ratio of  3 : 2

 

We have 5 equalline segments on AB    and   C are 3 of these

 

We can find the x coordinate of B, thusly :

 

[  -6 + (3/5) ( x coordinate of B -   - 6 ] =  3.6       add 6 to both sides

 

(3/5)(x coordinate of B  + 6 )  =  9.6      multiply both side by (5/3)

 

x coordinate of B + 6  =  16   subtract  6 form both sides

 

x coordinate of B  = 10

 

Similarly, we can find the y coordinate of B thusly.....

 

[ 5 + (3/5)( y coordinate of B - 5)  =  -0.4        subtract 5 from both sides

 

(3/5) (y coordinate of B - 5)  = -5.4       multiply both sides by 5/3

 

y coordinate of B - 5  = -9       add 5 to both sides

 

y coordinate of B  =  -4

 

So....B  =  ( 10 , - 4)   ⇒  "C"

 

See the graph, here : https://www.desmos.com/calculator/hfo8kkx0lp

 

 

cool  cool cool

 May 10, 2019

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