Please do the following: [br][br]1) Use the LINE tool [icon]https://www.geogebra.org/images/ggb/toolbar/mode_join.png[/icon] to construct 2 lines that intersect.[br]2) Use the INTERSECT tool [icon]https://www.geogebra.org/images/ggb/toolbar/mode_intersect.png[/icon] to plot the point at which these 2 lines intersect. [br][br]3) Use the ANGLE tool [icon]https://www.geogebra.org/images/ggb/toolbar/mode_angle.png[/icon] to measure any 2 angles that are not adjacent each other.

[color=#0000ff]When you're done (or if you're unsure of something), feel free to check by watching the quick silent screencast below the applet. [/color]