Answer:
Gọi AH là đường cao kẻ từ A đến BC
Xét tam giác AHC vuông tại H
Suy ra AH = HC. cotA= 9.cot35° = 12,9
Xét tam giác AHB vuông tại H
Suy ra BH = AH.tanA = 12,9.tan61°=23,37
Ta có BC= HC+ HB= 9+23,27 =32,27
Diện tích tam giác ABC = 1/2 × AH ×BC= 1/2 ×12,9×32,27=208,1415
CXB = 40 degrees
I am not positive but from what I have looked up this is the answer.
Answer:
- Part A: The price of fuel A is decreasing by 12% per month.
- Part B: Fuel A recorded a greater percentage change in price over the previous month.
Explanation:
<u>Part A:</u>
The function calculates the price of fuel A each month by multiplying the price of the month before by 0.88.
Month price, f(x)
1 2.27 (0.88) = 1.9976 ≈ 2.00
2 2.27(0.88)² = 1.59808 ≈ 1.60
3 2.27(0.88)³ = 1.46063 ≈ 1.46
Then, the price of fuel A is decreasing.
The percentage per month is (1 - 0.88) × 100 = 12%, i.e. the price decreasing by 12% per month.
<u>Part B.</u>
<u>Table:</u>
m price, g(m)
1 3.44
2 3.30
3 3.17
4 3.04
To find if the function decreases with a constant ration divide each pair con consecutive prices:
- ratio = 3.30 / 3. 44 = 0.959 ≈ 0.96
- ratio = 3.17 / 3.30 = 0.960 ≈ 0.96
- ratio = 3.04 / 3.17 = 0.959 ≈ 0.96
Thus, the price of fuel B is decreasing by (1 - 0.96) × 100 =4%.
Hence, the fuel A recorded a greater percentage change in price over the previous month.