Other - GeoGebra

Go to geogebra.org/classic and disable the grid and axes before starting these questions. Video here

  a - answer    s - solution    v - video

Question 1

Our aim is to show the sum of interior angles in a triangle is $180^{\circ}$

a) Construct a trianglea s v

b) Measure each anglea s v

c) Find the sum of these three anglesa s v

d) Move the vertices of the triangle to check the statement holds.a s v

Question 2

Our aim is to show Pythagoras' Theorem holds in a $3$, $4$, $5$ Triangle

a) Construct a line of length $3$a s v

b) Construct an angle of $90^{\circ}$a s v

c) By constructing a circle of radius $4$ at the right angle, construct a line of length $4$ that is perpendicular to the line of length $3$a s v

d) Complete the shape to form a triangle. Measure the last sidea s v

e) Confirm that the sum of the square of the two shorter sides is equal to the square of the longer sidea s v