Answer:
23
Step-by-step explanation:
133 = 18 + 5x
155 = 5x
23 = x
The left side can be written as a square. We can take the square root, then subtract 1.
... (x +1)² = 17
... x +1 = ±√17
... x = -1 ±√17
Answer:
c = 8.14 million×(0.9166)^t
4.83 million
Step-by-step explanation:
Data:
t = y - 2007
c₀ = 8.14 million
c₃ = 23 % less than c₁
Part 1. Calculate c₃
c₃ = c₀(1 - 0.23) = 0.77c₀
Part 2. Calculate r
c₃ = c₀r^t
0.77c₀ = c₀r³
0.77 = r³ Divided each side by c₀
r = 0.9166 Took the cube root of each side
The explicit decay model is c = 8.14 million×(0.9166)^t
Part 3. Prediction
t = 2013 - 2007 = 6
c = c₀r^t = 8.14 million×(0.9166)⁶ = 8.14 million × 0.5929 = 4.83 million
The model predicts that there will be 4.83 million cars for sale in 2013.
It shall be the letter ........b