Please solve q 76?

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1 Answer
Apr 18, 2018

The answer is #=3#

Explanation:

Let the mid-point of #BC# be

#P(3/2,-5/2)#

and

#G(p,q)#

#A(2,1)#

Then, by the definition of the centroid

#vec(AG)/vec(AP)=2/3#

Taking the x- coordinates

#(p-2)/(3/2-2)=2/3#

#p-2=2/3*-1/2=-1/3#

#p=2-1/3=5/3#

#vec(AG)/vec(AP)=2/3#

Taking the y-coordinates

#(q-1)/(-5/2-1)=2/3#

#q-1=2/3*-7/2=-7/3#

#q=1-7/3=-4/3#

Therefore,

#p-q=5/3-(-4/3)=5/3+4/3=9/3=3#