Answer:
Choice D is correct
Step-by-step explanation:
The eccentricity of the conic section is 1, implying we are looking at a parabola. Parabolas are the only conic sections with an eccentricity of 1.
Next, the directrix of this parabola is located at x = 4. This implies that the parabola opens towards the left and thus the denominator of its polar equation contains a positive cosine function.
Finally, the value of k in the numerator is simply the product of the eccentricity and the absolute value of the directrix;
k = 1*4 = 4
This polar equation is given by alternative D
Answer:
Maximum area possible
f(max) = 3906,25 ft²
Dimensions:
a = 62,5 ft
w = 62,5 ft
Step-by-step explanation:
Perimeter of the rectangular fencing P = 250 feet
And sides of the rectangle a and w (width of rectangle)
Then
A = a*w
2a + 2w = 250 ⇒ a = (250 -2w)/ 2 ⇒ a = 125 - w
f(w) = (125 - w ) *w f(w) = 125w - w²
Taking derivatives both sides of the equation
f´(w) = 125 - 2w f´(w) = 0 125 - 2w = 0
w = 125/2
w = 62,5 ft ⇒ a = 125 - 62,5
a = 62,5 ft
f(max) = ( 62,5)²
f(max) = 3906,25 ft²
Answer:
the answers are 13, ab/2, 20 and 15x²/2
Answer: 0.5143
Step-by-step explanation:
Probability of students who are over 21 years old = 30% = 0.3
Probability of students who are under 21 years old = 100% - 30% = 70% = 0.7
Probability of drinking alcohol for over 21 = 80% = 0.8
Probability of not drinking alcohol for over 21 = 100%- 80% = 20% = 0.2
Let the probability of the students who are not over 21, that drink alcohol be p.
Total probability of a college student drinking alcohol = (0.3 × 0.8) + (0.7 × p)
0.6 = (0.3 × 0.8) + (0.7 × p)
0.6 = 0.24 + 0.7p
0.7p = 0.6 - 0.24
0.7p = 0.36
p = 0.36/0.7
p = 0.5143
The probability of the students who are not over 21, that drink alcohol is 0.5143.
