Answer:
13.76 square meters
Step-by-step explanation:
The side of square is 8 meters.
So, the diameter of circle = 8 meters.
⇒ Radius = (diameter of circle) ÷ 2 = 8 ÷ 2 = 4 meters
Shaded region = Area of square - Area of circle
= (Side × Side) - π × (radius)²
= 8 × 8 - π × 4 × 4 {∵ π = 3.14 or 22÷7}
= 64 - 50.24
= 13.76 square meter
Use the next formula to find the margin or error:
z is the critical value (For a 95% confidence level the z-score is 1.95998)
σ is the standard deviation
n is the sample size
<h2>Then the margin of error is: 6.6639</h2>
If 2 sodas and 4 hamburgers are $12.00 and 4 sodas and 2 hamburgers are $9.00 how much is a single hamburger?
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2s + 4h = 12, (1) 4s + 2h = 9. (2) Multiply (1) by 2. You will get 4s + 8h = 24, (1') 4s + 2h = 9. (2') Distract (2') from (1'). You will get 8h - 2h = 24 - 9, or 6h = 15 ---> h =  =  = 2.5. Thus one hamburger price is $2.50. Then from (1) s =  = 1. Answer. One hamburger price is $2.50 and 1 soda costs $1.00.
There is even more elegant way to solve the problem.
Simply add all hamburgers and all sodas. 6 hamburgers and 6 sodas. $12 + $9 = $21.
Hence, 1 hamburger + 1 soda =  = $3.50.
Having this, everybody can solve to the end in this way, actually, without equations and using the mental math only.
Question: A man measures the angle of elevation to the top of a mountain to be 12 degrees. He drives 7 miles closer and finds the angle of elevation to be 37 degrees. How high is the mountain?
Answer:
x = 8
Step-by-step explanation
Complimentary angles have a sum of 90*. Thus when adding the two equations together, we must get 90*.
7x + 17 + 3x - 7 = 90 Combine like terms
10x + 10 = 90 Subtract 10 on both sides
10x = 80 Divide both sides by 10
x = 8
