Given: ABCD is a parallelogram. Angles Segments Triangles Statements Reasons
Prove: AB = CD and BC - DA
BAC
BCA
DAC
2DCA
B
с
Statements
Reasons
✓ 1. ABCD is a parallelogram
1. given
2. def. of parallelogram
✓ 2. AB || CD
✓ 3. BC || DA
✓ 4. draw AC
3. def. of parallelogram
4. unique line postulate
A
D
5. def. of alt. interior angles
✓ 5. BCA and DAC
are alt. interior angles

Step-by-step explanation:

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the answer is 31.27mph

geometry: triangles

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call the larger triangle abc

then the smaller triangle cde is similar to abc (all angles are equal, aaa).  

ab is the side that is 36, and we wish to find de, the side corresponding to ab

area_cde = area_abc - area_cde --> area_abc / area_cde = 2

let x=length of de

ratio of areas = (ratio of sides)^2

+2+=+%2836%2fx%29%5e2+

+2+=+1296%2fx%5e2+

++x%5e2+=+1296%2f2+=+648+

25.45584