Describe the pattern. that does not make sense to me at all

The pattern is multiplying by 2

Step-by-step explanation:

.41, .82,1.64,3.28,

Take the second term and divide by the first term

.82/.41 = 2

Take the third term  and divide by the second term

1.64/.82 = 2

Take the fourth term and divide by the third term

3.28/1.64 = 2

We are multiplying by 2 to get from the first to the second term, the second to the third term, the third to the fourth  term.  

b.my answer is b.

brainliest

we have three similar triangles, because each has a right angle and shares an angle.   let's write the angles in order: opposite to short leg, long leg, hypotenuse.

cab similar to bad similar to cbd

or as ratios,

ca: ab: cb = ba: ad: bd = cb: bd: cd

we also know

ac = ad + cd

(ad+cd): ab: cb = ba: ad: bd = cb: bd: cd

(ad+cd)/cb=cb/cd

we have cb=6, ad=5 and seek x=cd.

we reject the negative root and conclude x=4

answer: 4