Part of Shape, space and measures
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A short video on how to show the angles in a triangle add up to 180掳.
Click to see a step-by-step slideshow.
WHAT YOU NEED: piece of card/paper, ruler, scissors and pen.
STEP 1: Use the ruler to draw a straight horizontal line, draw a diagonal line from the end of the horizontal line...
...and draw another diagonal line to join the points and mark the angles inside the triangle. Use the scissors to cut the triangle out.
STEP 2: On another piece of paper, use the ruler to draw another horizontal line.
STEP 3: Tear each corner off the triangle.
STEP 4: Place two of the triangles along the horizontal line. Turn the third triangle upside down and slot it between the other two on the line. It should fit perfectly.
The angles in the triangle you drew all add up to 180掳. Remember, all angles on a straight line add up to 180掳.
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