Answer: Choice D) 7.5 cm
==========================================================
Step-by-step explanation:
We are told that quadrilateral ABCD is similar to quadrilateral EFGH.
The order of the four letter sequence is important.
- For ABCD, we have AB as the first pair of letters.
- For EFGH, we have EF as the first pair of letters.
Therefore, AB and EF are corresponding sides.
So AB = 10 and EF = x pair up together. We can form the ratio AB/EF which becomes 10/x.
The diagram shows that AD = 8. Notice that A and D are the first and last letters of ABCD. The first and last letters of EFGH are E and H. We can see that AD and EH correspond to one another because of this.
AD = 8 and EH = 6 forming the ratio AD/EH = 8/6
Because the quadrilaterals are similar, the corresponding ratios must be the same. Therefore, AB/EF is the same as AD/EH.
-----------------------
Let's set up a proportion to solve for x
AB/EF = AD/EH
10/x = 8/6
10*6 = x*8
60 = 8x
8x = 60
x = 60/8
x = 7.5 Answer is choice D