- #1

Julian102

- 17

- 1

## Homework Statement

If two vertex of a square of the side AB is A(1,2) and B(2,4) find other two vertex C and D?

## Homework Equations

1. y-y1 = m ( x-x1)

2. m=y1-y2 / x1-x2

3. m1*m2= -1

4. (x-x1) / (x1-x2) =(y-y1)/(y1-y2)

5. m=tanA

6. If ax+by+c=0 then its parallel line is ax+by+k=0

## The Attempt at a Solution

Equation of AB is can be found using formula 4 , then slope is found using formula 2 . Then slope of perpendicular is -1/m (formula 3) . Now perpendicular AD and BC can be found using formula 1 . Now CD is parallel to AB . I need to find CD ...The distance between AB and CD is root 5 (of course since distance between AB is root 5 and it is a square) ...Please tell me how to find the side CD ...and diagonals AC and BD ...