Rectangle rearrangement
A 3x8 rectangle is cut into two pieces... then rearranged to form a right-angled triangle. What is the perimeter of the triangle formed?
Problem
A $3 \times8$ rectangle is cut into two pieces along the dotted line shown. The two pieces are then rearranged to form a right-angled triangle. What is the perimeter of the triangle formed?
Image
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If you liked this problem, here is an NRICH task which challenges you to use similar mathematical ideas.
Student Solutions
The diagram shows the two pieces will fit together to form a right-angled triangle which has a base $8$ and height $6$. The length of the hypotenuse = $\sqrt{(6^2+8^2)}$, that is $10$, so the perimeter of the triangle is $24$.
Image
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