Answer:
7 feet is the length of the blade of the windmill.
Step-by-step explanation:
We have the equation
h = 7 sin(pi/21t) + 28 ------ eq1
At time 't' = 0, the end of the blade is pointing to the right parallel to the ground meaning it is at the same height as the other end. (Ф = 0°)
So, by calculating the maximum height of this end at Ф = 90°. we can calculate the length of the blade.
Now, we know that a general model equation of a circular simple harmonic motion is represented as : y = A sinωt + k ----- eq2
Where A is the amplitude that is, maximum displacement from mean to maximum position.
ω is the angular frequency.
Comparing eq1 and eq2:
A = 7
so the difference in blades end height at Ф = 0° and Ф = 90° is 7 feet.
Hence, the length of the blade is 7 feet.
Answer: 34
Step-by-step explanation:
The expression x( x - 4 ) when expanded is x² - 4x
An expression, often known as a mathematical expression, is a finite collection of symbols that are well-formed in accordance with context-dependent principles.
When a bracket is expanded, each term is multiplied by the expression outside of the bracket.
The distributive property states that multiplying the sum of two or more addends by a number yields the same outcome as multiplying each addend separately by the number and combining the resulting products.
Consider the expression,
x( x - 4 )
Let us assume y = x( x - 4 )
Using the distributive property, a( b + c ) = ab + ac
y = x( x - 4 )
y = x · x - x · 4
y = x² - 4x
Therefore, x( x - 4 ) = x² - 4x
Therefore, the expression when expanded is x² - 4x.
Learn more about expression here:
brainly.com/question/1859113
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The answer is Infinate Solutions I believe we are working on these types of equations in school rn
Answer: $75 + $65w ≥ $635
Step-by-step explanation:
$635 is your goal and how much money you should earn
$75 is your already saved money
$65 is how much you're going to save every week
Ask yourself, how many weeks do you have to save money before you reach your goal of $635. Since we don't know this value, it's a variable, w.
