Answer:
B.
Step-by-step explanation:
Draw the radius starting at the right endpoint of the chord to the center of the concentric circles.
Draw a line going from the center to the point on the inner circle. Notice that since a chroad and radius intersect, this form a right angle.
You could also look at this as a tangent line passeing through the inner circle, this conforming this angle as a right angle.
Now, finally, notice that the two triangles we got are similar due to SAS. Thus, if we find the value of one part of x, we can get the other part of x.
Looking at one part of the triangle, we get a 6-x-10 triangle so using the Pythagorean theorem
[tex] {6}^{2} + {x}^{2} = {10}^{2} [/tex]
[tex] {x}^{2} = 64[/tex]
[tex]x = 8[/tex]
Doubling that gives us
16.
