Posted by **lana** on Wednesday, July 25, 2007 at 2:18pm.

ABCD is a square . if the coordinates of three of its vertices are A(-1,2a), B(a,2a), C(a,0), find the coordinates of D.

BC is obviously 2a (it's a vertical line)

then AB must be 2a (notice AB is horizontal)

so BC = AC because it is a square

2a = a+1

a=1

Now you can find the coordinates of A, B, and C, it should be easy for you to find D.

## Answer this Question

## Related Questions

- Geometry - The coordinates of the three vertices of a square ABCD are A (-3, 5...
- math - hi i will ask u in math :) in (( distance between two points )) * three ...
- geometry - In rectangle ABCD, if the coordinates of A are (0, 0) and the ...
- math - In rectangle ABCD, if the coordinates of A are (0, 0) and the coordinates...
- geometry - Triangle PQR has vertices P(1,2), Q(25,2) and R(10,20). Find the ...
- Geometry - The coordinates of the vertices of quadrilateral ABCD are A (-8, 8...
- math - Triangle ABC below is reflected across the y-axis and then translated 1 ...
- Geometry - I need help with vertices! The vertices of triangle FGH are F(1,1), G...
- geometry - In parallelogram ABCD, A (0,0),B(a,b)and D(c,0)are three of it's ...
- geometry - In parallelogram ABCD, A (0,0),B(a,b)and D(c,0)are three of it's ...