Find the perimeter of the triangle whose sides are (1,2) , (3,4) and (-1,5)

Given the perimeter whose edges are the point A(1,2),
B(3,4) and C(-1,5)

We need to find the perimeter of the
triangle.

First we need to find the length of the
sides

==> We will use the distance between two
points formula to calculate the length of the
sides.

==> AB = sqrt( 3-1)^2 + (4-2)^2 = sqrt(8) =
2sqrt2

==> BC = sqrt(3+1)^2 + (4-5)^2 =
sqrt(17)

==> AC = sqrt(1+1)^2+(2-5)^2 =
sqrt(13)

Then the perimeter
is:

P = AB + BC +
AC

  = 2sqrt2 + sqrt17 +
sqrt13

= 2.83 + 4.12 + 3.61 =
10.56 ( approx.)