Question

What is the length of segment DA?

Answer 1

Answer: DA = 6

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Step-by-step explanation:

The triangles are similar, allowing us to make the proportion below

DB/DA = DA/DC

Plug in the given values. Cross multiply and solve for x

DB/DA = DA/DC

9/DA = DA/4

9*4 = (DA)*(DA)

36 = (DA)^2

(DA)^2 = 36

DA = sqrt(36)

DA = 6

The length of DA is exactly the geometric mean of the lengths BD and DC

geometric mean of x and y = sqrt(x*y)

Answer 2

Step-by-step explanation:

The length of this line segment is the distance between its endpoints A and B. So, a line segment is a piece or part of a line having two endpoints. Unlike a line, a line segment has a definite length.