Jamie's mother is making a quilt. the block shown below is made from a series of similar triangles

Step-by-step explanation:

To find B, C and D

we make use of Pythagoras theorem

since the line A = 8.5inch and looking at critically we can see the 3 inch meet it at the center (we divide 8.5 inch into 2 to give 4.25inch)

using Pythagoras theorem

hypothenus² = opposite²+adjacent²

4.25² = 3²+b²

18.0625 - 9 = b²

9.0625 = b²

b = √9.0625 = 3.0103986447≈3.01

for c

3² + 3.01² = C²

9 + 9.0601 = 18.0601 = C²

C = √18.0601 = 4.24971763768 ≈ 4.25

C is a portion of the longest side meaning it will need to be divided by 2 = 4.25/2 = 2.125

to get D

2.125² = 1.5² + D²

4.25 = 2.25 + D²

4.25 - 2.25 = D²

2 = D²

D = √2 = 1.41421356237 ≈1.41