You would subtract.
The question is asking who has more, so to find out, you need to take away the smaller amount from the bigger amount. (1.25-1.05)
So Sandra bought more candy. Hope this helps!
Part a)
Answer: 5*sqrt(2pi)/pi
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Work Shown:
r = sqrt(A/pi)
r = sqrt(50/pi)
r = sqrt(50)/sqrt(pi)
r = (sqrt(50)*sqrt(pi))/(sqrt(pi)*sqrt(pi))
r = sqrt(50pi)/pi
r = sqrt(25*2pi)/pi
r = sqrt(25)*sqrt(2pi)/pi
r = 5*sqrt(2pi)/pi
Note: the denominator is technically not able to be rationalized because of the pi there. There is no value we can multiply pi by so that we end up with a rational value. We could try 1/pi, but that will eventually lead back to having pi in the denominator. I think your teacher may have made a typo when s/he wrote "rationalize all denominators"
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Part b)
Answer: 3*sqrt(3pi)/pi
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Work Shown:
r = sqrt(A/pi)
r = sqrt(27/pi)
r = sqrt(27)/sqrt(pi)
r = (sqrt(27)*sqrt(pi))/(sqrt(pi)*sqrt(pi))
r = sqrt(27pi)/pi
r = sqrt(9*3pi)/pi
r = sqrt(9)*sqrt(3pi)/pi
r = 3*sqrt(3pi)/pi
Note: the same issue comes up as before in part a)
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Part c)
Answer: sqrt(19pi)/pi
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Work Shown:
r = sqrt(A/pi)
r = sqrt(19/pi)
r = sqrt(19)/sqrt(pi)
r = (sqrt(19)*sqrt(pi))/(sqrt(pi)*sqrt(pi))
r = sqrt(19pi)/pi
C. 2(x+10) is the correct answer
f(x) = 7x - 1
-2 = 7x - 1
-2 + 1 = 7x
-1 = 7x
x = -1/7
0 = 7x - 1
1 = 7x
x = 1/7
4 = 7x - 1
4 + 1 = 7x
5 = 7x
x = 5/7
8 = 7x - 1
8 + 1 = 7x
9 = 7x
x = 9/7
So the domain is
Domain = {-1/7, 1/7, 5/7, 9/7}
First remove the parenthesis.
5/6 - 2/3
Then we want the least common denominator which is 6 because 2 * 3 = 6.
Now we want to adjust the fractions based on our LCD.
So 5/6 - 2 * 2/6
Now since the denominators are equal we can combine the numerators.
So 5 - 2 * 2/6
First multiply 2 by 2 to get 4. Our expression then becomes 5 - 4/6 which translates to 1/6.
Hope this helps!