PointsPoints
You can make a point in GeoGebra in two different ways. On one hand you can
use the 
New Point tool, on the other hand you can enter a point in the Input bar. If
you want a point A with coordinates (-2,3), you enter A=(-2,3)
in the input bar.
You can find the coordinates of a point A by using one of the commands x(A)
or y(A).
Exercise 1
Make a point A by using the
New Point tool. Make another point B by entering
B=(x(A)+1,y(A)) and a point C by entering C=(2,y(A)).
Move A!
Exercise 2
Make a point A by using the
New Point tool. Make another point B by entering B=(y(A),x(A)).
Put a trace on A and B (right-click one each point). Move A!
Exercise 3
Make a point A by using the
New Point tool.
Make another point B by entering appropriate code in the input bar, B should be the reflection A in the y-axis.
Make another point C by entering appropriate code in the input bar, C should be the reflection A in the x-axis.
Make another point D by entering appropriate code in the input bar; D should be the point you get from first reflecting A in the y-axis, then in the x-axis.
Put traces on all four points. Move A!
