What is the length of the line segment fg with f(2,-7) and g(-7,8) ?

Given the endpoints of a line segment fg is f(2,-7) and
g(-7,8).

We need to find the length of the line
fg.

We will use the distance between two points formula to
calculate the length.

We know
that:

D = sqrt[ (x1-x2)^2 + (y1-y2)^2
]

==> l fg l = sqrt[(2+7)^2 +
(-7-8)^2'

==> l fg l = sqrt[ (9^2 + (-15)^2
]

==> l fg l =
sqrt(81+225)

==> l fg l = sqrt(306) =
17.49

Then the length of the line segment fg
is sqrt(306)=17.49 units.