A = 4πr² Divide both sides by 4π
A / 4π = r² Find the square root of both sides
√(A / 4π) = √(r²) Cancel out the square with the square root
√(A / 4π) = r Switch the sides to make it easier to read
r = √(A / 4π)
<h3>
Answer: $2400</h3>
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Explanation:
x = Mason's salary in dollars for that month
x/6 = one-sixth of his salary
x/6+800 = total amount spent (the x/6 dollars and $800 combined)
In total, he spent half his salary. This means he spent x/2 dollars for the month overall.
Set the two items equal to one another. Solve for x.
x/6 + 800 = x/2
6(x/6 + 800) = 6*(x/2) ... see note at the bottom of the page
x+4800 = 3x
4800 = 3x-x
4800 = 2x
2x = 4800
x = 4800/2
x = 2400
His monthly salary is $2400
1/6 of this is (1/6)*2400 = 2400/6 = 400 dollars. Add on the $800 he also spent to get a total of 400+800 = 1200 dollars spent, which is exactly one half of the $2400. The answer is confirmed.
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Note: I multiplied both sides by 6 to clear out the fractions. The value 6 is the LCD in this case.
Answer:
Step-by-step explanation:
1) y = 50x + 2500
2) y = 200x + 1000
if we build a system with the two equations, we have:
50x+2500 = 200x + 1000
150x = 1500
x = 10
y = 2000 + 1000 = 3000
3) 10
4) $3000
A) We know that

where d

= distance,
v = velocity,
t = time
In this case, d = 2 mi., t = 30 min. So we get

Dividing both sides by 30, we get

Thus a function for his walk would be

where y = distance and x = number of minutes he walks.
b) Domain of a function is a set of x-values on which the function defined. In this case, the number of minutes is 30 at maximum. So the domain of the function is [0, 30].
Perimeter is just the addition of the side lengths so add them together:
5c+6 + 2c+5 = 7c+11
Option D.