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Question from Amanda, a parent:
what is the area of a circle with a circumference of 3000 metres?
Amanda,
The area of a circle is given by the formula A = π r2, where A is the area and r is the radius. The circumference of a circle is C = 2 π r.
If we "solve for r" in the second equation, we have r = C / (2 π ). Now we use this to replace r in the first equation: A = π [ C / (2 π ) ]2.
When we simplify this, we get A = C2 / (4 π).
Now you can put your value of C into this equation and find A. Remember, π is about 3.1416.
The first step to solving an equation like this is to find the slope of a line that will be perpendicular to the line given. The slope of a line that's perpendicular to another line is the negative reciprocal. The negative reciprocal of -1/5 is 5. So, so far our equation is y = 5x + b. Now, to find what b is equal to, we should substitute the values of x and y from the point (1,2) since we know that our line goes through the point. Our equation becomes:
2 = 5 + b
b= -3
That means that the equation of our new line is y = 5x - 3
Answer:
The answer to your question is below
Step-by-step explanation:
csc α - cot α = 
Work with the left part

Simplify

Multiply by the reciprocal
Simplify

Remember that
sin²α = 1 -cos²α
Substitute the previous equation

Simplify
The identity i proved.
Answer:
6/9 = 2/3
Step-by-step explanation:
1/3 = 3/9
3/9 = 3/9
3/9 + 3/9= 6/9 = 2/3
8/3=3x (cross multiplied to get this)
X=8/9 (divided both sides by 3)
Hope this helps :)