A triangle has corners at #(3 ,4 )#, #(6 ,3 )#, and #(2 ,7 )#. How far is the triangle's centroid from the origin?

1 Answer
Apr 4, 2016

≈ 5.935 units

Explanation:

The first step is to find the coordinates of the centroid.

If #(x_1,y_1),(x_2,y_2)" and " (x_3,y_3) #
are the coordinates of the vertices of a triangle , then

x-coord#(x_c) = 1/3(x_1+x_2+x_3)" and " #
y-coord# (y_c) = 1/3(y_1+y_2+y_3) #

here #x_c = 1/3(3+6+2) = 11/3" and " y_c = 1/3(4+3+7) = 14/3 #

coords of centroid # = (11/3 , 14/3 ) #

To calculate the distance the centroid is from the origin use the #color(blue)" distance formula " #

#d = sqrt((x_2 - x_1)^2 + (y_2 - y_1)^2 )#

where #(x_1,y_1)" and " (x_2,y_2)" are 2 coord points "#

The 2 points here are the centroid and the origin.
Since the origin is one of the points this simplifies the distance formula to :

#d = sqrt((11/3)^2 + (14/3)^2) = sqrt((121/9)+(196/9))#

# = sqrt(317/9) ≈ 5.935" units " #