Answer:
Diameter = 9
Step-by-step explanation:
Let the diameter be represented as x.
Based on the secant-tangent theorem, the following equation representing the relationship between the segments would be:
(16 + x)(16) = 20²
256 + 16x = 400
Subtract 256 from each side
16x = 400 - 256
16x = 144
Divide both sides by 16
x = 144/16
x = 9
Diameter = 9
Actually I think it may be C
Let's call our number <em>x</em>.
So we can setup the equation x² = 100.
To solve this equation, we square root both sides.
So we have x = ±10.
Always use plus or minus when square rooting both sides
of an equation so our answer is not only 10, it's also -10.