Answer:
k = 11/3
Step-by-step explanation:
If the line is tangent to the curve, then Δ = 0.
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Remembering:
Δ>0 two different points of intersection x' x''
Δ=0 one point of intersection x' = x''
Δ<0 two different points of intersection in the complex plan x' and -x'
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As the line and the curve have one point of intersection, which is (x, y), we can make a equality between them:
2x + k = 3x² + 4
0 = 3x² - 2x + (4 - k)
Now we can use the Δ=0 (Δ= b² - 4ac)
Δ = 0 = (-2)² - 4.3.(4-k)
0 = 4 - 48 + 12k
12k = 44
k = 44/12 = 2 . 22 /3. 2.2 = 22/3.2 = 11/3
k = 11/3
Answer:
The price of the admission is 15.
Step-by-step explanation:
From the information given, you can write the following equations:
a+3e=45 (1)
a+5e=65 (2), where:
a is the admission cost
e is the exhibition cost
First, you can solve for a in (1):
a=45-3e (3)
Second, you can replace (3) in (2):
45-3e+5e=65
45+2e=65
2e=65-45
2e=20
e=20/2
e=10
Finally, you can replace the value of e in (3):
a=45-3e
a=45-3(10)
a=45-30
a=15
According to this, the price of the admission is 15.
First, we get ax^2+bx+c. Next, we know that the line of symmetry is -b/2a. Since we know that there is a maximum value, the parabola is facing downwards, so a is negative. For random numbers, we can say that a = -0.5 and b=-10 (b needs to be negative for -b/2a to equal -10), getting -0.5x^2-10x+c. Plugging -10 in for x (since -10 is the middle it is the max), we get -50+100=50. Since the maximum needs to be 5, not 50, we subtract 45 from the answer to get it and therefore make c = -45, getting -0.5x^2-10x-45
E. 72
6 feet long cast shadow = 24 feet pole
18 feet long cast shadow = 72 feet pole
18/6=3
24x3=72