The function is:
B ( t ) = 4 * e^(0.8 t)
4 * e^(0.8 t) = 400
e^(0.8 t) = 400: 4
e^(0.8 t) = 100 / ln
ln e^(0.8 t) = ln 100 ( and since: ln e = 1 and ln e^x = x * ln e )
0.8 t = 4.6
t = 4.6 : 0.8 = 5.76 ≈ 6
Answer:
D ) 6 hours.
1. She can travel 18 miles. Subtract 35 - 2 (initial fee) to have 33. divide 33 by 1.75 to get 18.85. To check how much her total would be, use inverse operations. 18.85 * 1.75 = 32.9875. 32.9875 + 2 = 34.9875. It is barely under $35 but still in her budget.
2. 20m * $1.75 = $35. $70 - $35 = $35. Yes, she can cover the fare. Samantha has more than needed. She can afford the taxi fare and still have money left for future use.
Answer:
1)Area; A = ¼πr²
Perimeter; P = πr/2 + 2r
2)A = 19.63 cm²
P = 17.85 cm
3) r = 8.885 cm
4) r = 14 cm
Step-by-step explanation:
This is a quadrant of a circle. Thus;
Area of a circle is πr². A quadrant is a quarter of a circle. Thus;
Formula for Quadrant Area is; A = ¼πr²
A) Perimeter of a circle is 2πr. Thus, perimeter of a quadrant is a quarter of the full circle perimeter.
Formula for the quadrant perimeter in the image given is;
P = 2πr/4 + 2r
P = πr/2 + 2r
B) When r is 5 cm;
A = ¼π(5)²
A = 19.63 cm²
P = π(5)/2 + 2(5)
P = 17.85 cm
C) when A is 100cm²:
¼πr² = 100
r² = 100 × 4/π
r² = 78.9358
r = √78.9358
r = 8.885 cm
D) when P = 50 cm.
50 = πr/2 + 2r
50 = (½π + 2)r
r = 50/(½π + 2)
r = 14 cm
