A triangle has corners at (8, 5 ), ( 2, -7), and ( 1, -2 )#. If the triangle is reflected across the x-axis, what will its new centroid be?
1 Answer
May 18, 2018
Explanation:
"begin by calculating the coordinates of the centroid"
"given the coordinates of the vertices of a triangle say"
(x_1,y_1),(x_2,y_2)" and "(x_3,y_3)
"then the centroid is the average of the x and y"
"coordinates of the vertices"
"centroid "=[1/3(x_1+x_2+x_3),1/3(y_1+y_2+y_3)]
rArr[1/3(8+2+1),1/3(5-7-2)]=(11/3,-4/3)
"under a reflection in the x-axis"
• " a point "(x,y)to(x,-y)
rArr(11/3,-4/3)to(11/3,4/3)larrcolor(red)"new centroid"
