He spent 1.25 hours edging.
You can get this by multiplying the total amount of time by the percentage.
.25 * 5 = 1.25
Answer:
y-intercept: (0, 75) ⇒ y = 75
x-intercepts: (3, 0) and (5, 0) ⇒ x = 3 and x = 5
vertex: (4, -5)
Step-by-step explanation:
Let the x-axis be the ground (when y = 0). Therefore underground when y < 0 and overground when y > 0
The function is a quadratic: f(x) = ax² + bx + c
If the coaster enters the tunnel three seconds after the first descent starts and stays in the tunnel for a total of 2 seconds, then y = 0 when x = 3 and x = 5
Also, when x = 1, y = 40
- f(3) = 0
⇒ 9a + 3b + c = 0
- f(5) = 0
⇒ 25a + 5b + c = 0
- f(1) = 40
⇒ a + b + c = 40
Solve 2 equations simultaneously:
- 9a + 3b + c = 0
- 25a + 5b + c = 0
- a + b + c = 40
⇒ a = 5 b = -40 c = 75
⇒ f(x) = 5x² - 40x + 75
<u>y-intercept</u>
when x = 0
⇒ f(0) = 5(0²) - 40(0) + 75 = 75
⇒ y-intercept = (0, 75)
<u>x-intercepts</u>
x = 3 and x = 5
<u>Vertex</u>
If the x-intercepts are when x = 3 and x = 5, then vertex is when x = 4
⇒ f(4) = 5(4²) - 40(4) + 75 = -5
⇒ vertex = (4, -5)
I did the calculations of A(t)=50(0.8)5
and i got 200 for the 50*0.8*5
and the A(t) is 1,000
Hope i could help :D
So your gonna Multiply each term in the first parentheses by each term in the second parentheses “ -5x5-5i-5x2i-2ix i ” than multiply the numbers “ -25 -5i -5x2i -2ixi ” that’s your answer!
The size of the sample they should take to estimate p with a 2% margin of error and 90% confidence is n = 1691.
In statistics, the margin of error is just the degree of a significant error in the outcomes of random sample surveys.
The formula of margin error is, E = z√((p-vector)(1 - (p-vector)) ÷ n)
E = 2% = 0.02
Confidence level = 90%
Now, the proportion is not given so adopt nominal (p-vector) = 0.05
The critical value at CL of 90% is 1.645.
Thus, making n the subject,
n = z²(((p-vector) × (1 - (p-vector))) ÷ E²)
n = 1.645²((0.5 × 0.5) ÷ 0.02²)
n = 1691.266
n ≈ 1691
Read more about the margin of error at
brainly.com/question/16141482?referrer=searchResults
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