A. X is the number of years after 2000
2006-200 = 6 years.
Replace x with 6 and solve:
105(6)^2 + 680(6) + 4296 = 12,156
Answer for part a: 12,156
Answer for part B.
There was just over 12,000 in 6 years , to get to 21,500 would be a little over 9,000 more 9/12 = 0.75
6 years x .75 = 4.5 years
6 + 4.5 = 10.5 years round to 10 years for estimating purposes
Answer for part b: about 10 years
Answer:
20°
Step-by-step explanation:

5 ideas
1.SSS (side, side, side) SSS stands for "side, side, side" and means that we have two triangles with all three sides equal. ...
2.SAS (side, angle, side) ...
3.ASA (angle, side, angle) ...
4.AAS (angle, angle, side) ...
5.HL (hypotenuse, leg)