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# Pythagoras perimeter question help watch

1. Question, Jack runs around the perimeter of a triangular field that measures 120cm by 46cm. On Sunday he decides to run the length followed by the width, but then cut back across the diagonal. How much shorter is this route than the whole perimeter?
2. (Original post by SBizzy)
Question, Jack runs around the perimeter of a triangular field that measures 120cm by 46cm. On Sunday he decides to run the length followed by the width, but then cut back across the diagonal. How much shorter is this route than the whole perimeter?
What have you attempted so far?
3. (Original post by Y11_Maths)
What have you attempted so far?
I attempted 120^2 + 46^2 = 16516. Square root of 16516 =128.514 and 120^2 - 46^2 =12284 square root of 12284 = 110.833, then I think I have to find the difference.
4. (Original post by SBizzy)
I attempted 120^2 + 46^2 = 16516. Square root of 16516 =128.514 and 120^2 - 46^2 =12284 square root of 12284 = 110.833, then I think I have to find the difference.
Well by the whole perimeter I’m assuming he runs round a rectangle with sides 120 and 46. So add up these and multiply by 2 to find the whole perimeter. Now use Pythagoras so find the diagonal distance (you’ve already done that). Then add the 3 side lengths of your triangle together and subtract that from the perimeter of your rectangle. Make sure you convert to metres though!
5. (Original post by Y11_Maths)
Well by the whole perimeter I’m assuming he runs round a rectangle with sides 120 and 46. So add up these and multiply by 2 to find the whole perimeter. Now use Pythagoras so find the diagonal distance (you’ve already done that). Then add the 3 side lengths of your triangle together and subtract that from the perimeter of your rectangle. Make sure you convert to metres though!
What are the the 3 side lengths? I added up all the sides to find the whole perimeter
6. (Original post by SBizzy)
What are the the 3 side lengths? I added up all the sides to find the whole perimeter
Like I said I assumed the whole perimeter is a rectangle because the question doesn’t make much sense otherwise. So think of it as a rectangle, fine the full perimeter, then use Pythagoras and calculate the triangles perimeter and subtract them
7. (Original post by Y11_Maths)
Like I said I assumed the whole perimeter is a rectangle because the question doesn’t make much sense otherwise. So think of it as a rectangle, fine the full perimeter, then use Pythagoras and calculate the triangles perimeter and subtract them
I got 478.694
8. (Original post by SBizzy)
I got 478.694
How?
It should be around 0.4m if I’m correct

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