Answer:
use sugar and release carbon
Step-by-step explanation:
Animals they eat and then release carbon through respiration. Nitrogen is only in the nitrogen cycle, and the only living organisms that can release oxygen are plants because humans and animals cannot photosynthesize. LOL!
Amount of pizza eaten by Charlie.
7/6× 22/7 × (101/2)² =9350.91667
Amount of pizza eaten by Julie
5/12 × 22/7 × 90.5² = 10725.3273
Answer = Julie
We can set up an equation to solve this problem, but first we need to write out what we know.
$20 overall
$0.24 every minute
$13.52 remaining on the card
Now that we know our information, we can set it up in an equation.
20 - 0.24x = 13.52
The 20 represents $20 overall when she first got the phone card.
We are then subtracting $20 from how must it costs a minute (which is 24 cents). The 'x' indicates the number we are trying to find (how many minutes her call lasted). Lastly, 13.52 is the result of everything, since she has $13.52 remaining on the card.
We can now solve the equation:
20 - 0.24x = 13.52
-0.24x = 13.52 - 20 /// subtract 20 from each side
-0.24x = -6.48 /// simplify
x = 27 /// divide each side by -0.24
Our solution is: x = 27.
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An easier way to solve this problem would be to first, subtract the total amount of money she had on the card when she first got it, and then the remaining total she ended up with.
$20 - $13.52 = $6.48
So, she spent a total of $6.48 on long distance calls, but since we are looking for how many minutes, we need to divide the total she spent and how much it costs per minute.
6.48 ÷ 24 = 27
We receive the same amount of minutes spent just like we did the last way we solved.
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Salma spent 27 minutes on the phone.
Answer:
Wdym? Do you have another question on your pf or something?
Step-by-step explanation:
Let me know if I can help!
Have a nice day <3
I will explain you and pair two of the equations as an example to you. Then, you must pair the others.
1) Two circles are concentric if they have the same center and different radii.
2) The equation of a circle with center xc, yc, and radius r is:
(x - xc)^2 + (y - yc)^2 = r^2.
So, if you have that equation you can inmediately tell the coordinates of the center and the radius of the circle.
3) You can transform the equations given in your picture to the form (x -xc)^2 + (y -yc)^2 = r2 by completing squares.
Example:
Equation: 3x^2 + 3y^2 + 12x - 6y - 21 = 0
rearrange: 3x^2 + 12x + 3y^2 - 6y = 21
extract common factor 3: 3 (x^2 + 4x) + 3(y^2 -2y) = 3*7
=> (x^2 + 4x) + (y^2 - 2y) = 7
complete squares: (x + 2)^2 - 4 + (y - 1)^2 - 1 = 7
=> (x + 2)^2 + (y - 1)^2 = 12 => center = (-2,1), r = √12.
equation: 4x^2 + 4y^2 + 16x - 8y - 308 = 0
rearrange: 4x^2 + 16x + 4y^2 - 8y = 308
common factor 4: 4 (x^2 + 4x) + 4(y^2 -8y) = 4*77
=> (x^2 + 4x) + (y^2 - 2y) = 77
complete squares: (x + 2)^2 - 4 + (y - 1)^2 - 1 = 77
=> (x + 2)^2 + (y - 1)^2 = 82 => center = (-2,1), r = √82
Therefore, you conclude that these two circumferences have the same center and differet r, so they are concentric.
