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joy_c_0612
Feb 17, 2007, 09:40 PM
hi! This is the problem included in a math contest of my brother. Could you please help me with this one.

Given coordinates A(-5,2) and B(5,7) and Ax/xB = 2/3, find the coordinates of x.

galactus
Feb 18, 2007, 06:49 AM
Set up a small system of equations.

A=(-5,2)
B=(5,7)

[-5,2]*[x,y]=2
[5,7]*[x,y]=3

Can you continue?

sohini1985
Feb 18, 2007, 07:11 AM
hi! this is the problem included in a math contest of my brother. could you please help me with this one.

Given coordinates A(-5,2) and B(5,7) and Ax/xB = 2/3, find the coordinates of x.
[-5,2]*[x,y]=2
[5,7]*[x,y]=3

solve like this

galactus
Feb 18, 2007, 07:19 AM
Yes, I got x=-8/45 and y=5/9.

Using the dot product.

[-5,2]*[-8/45,5/9]=2
[5,7]*[-8/45,5/9]=3