Answer:
B. 18
Step-by-step explanation:
Given:
There are two chord in the circle.
These chords are divided in two segments.
Segments of 1 chord is 21 and 6.
Segments of 2 chord is x and 7.
Now by using Intersecting Chord Theorem which states,
"When two chords intersect each other inside a circle, the products of their segments are equal."
Hence from above theorem we can say that;

Hence the Value of x is 18.
The y intercept is 17. You can see it clearly in the equation.
3300-20%=2640
$2640 is the answer to your question,hope this helps!please award brainliest??