Question

Quadrilateral ABCD with vertices A(4, 3), B(4, -2), C(-4, -2) and D(-4, 3) is a rectangle, find the length of the diagonals.

Answer 1

use the distance formula to find the distance from A to C

Answer 2

d = sqrt( (x2 - x1)^2 + (y2 - y1)^2 )

d = sqrt( (-4 - 4)^2 + (-2 - 3)^2 )

d = sqrt( (-8)^2 + (-5)^2 )

d = sqrt( 64 + 25 )

d = sqrt( 89 )

So that's the length of AC, which is one of the diagonals

Answer 3

I'll let you do the other diagonal

Answer 4

That made no sense to me..

Answer 5

have you heard of the distance formula before?

Answer 6

I dunno what it is

Answer 7

alright, it's just a formula to calculate the distance between any two points

Answer 8

if you never seen it before, then I suggest looking at this page

http://www.purplemath.com/modules/distform.htm

it gives a good visual tutorial on how it works