How do you find the perimeter of the triangle whose vertices are these specific points on a plane (-1,6) (4,-5) (-2, -4)?

1 Answer
Oct 20, 2015

A little over #28#


The perimeter is going to be equal to the sum of the lengths of the sides, which can be found by using the distance formula;

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

Plugging in the points for the first two vertices, we get;

#d_1=sqrt((4+1)^2 +(-5-6)^2)=sqrt(146)~=12#

For the second two;

#d_2=sqrt((-2-4)^2+ (-4+5)^2)=sqrt(37)~=6#

And for the last pair;

#d_3=sqrt((-2+1)^2 + (-4-6)^2)=sqrt(109)~=10#

So the sum of the three sides is roughly;


You can get a more accurate decimal approximation by using a calculator to evaluate the square root values above instead of approximating them.