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.
Answer:
ovlivia makes more per hour than kayle
Step-by-step explanation:
ovlivia makes $8.75 per hour while Kayle makes $8.5 per hour
Answer:
o your questions about snow: Is it ever too cold to snow? ... No, it can snow even at incredibly cold temperatures as long as there is some source ... area of the United States, see the average snowfall total table for hundreds of ... Seven days? ... Finally, a Winter Weather Advisory is issued for accumulations of snow
Step-by-step explanation:
The area of the regular heptagon which has a radius of approximately 27.87 cm and the length of each side is 24.18 cm is 2125 cm².
<h3>What is the area of a heptagon?</h3>
Heptagon is the closed shape polygon which has 7 sides and 7 interior angles.
The area of the regular heptagon is found out using the following formula.
Here, (<em>a</em>) is the length of the heptagon.
A regular heptagon has a radius of approximately 27.87 cm and the length of each side is 24.18 cm. Put the value of side in the above formula,
Hence, the area of the regular heptagon which has a radius of approximately 27.87 cm and the length of each side is 24.18 cm is 2125 cm².
Learn more about the area of a heptagon here;
brainly.com/question/26271153
So you ave a 3 out of 10 chance to get a letter in eh word DIG then you have a 1 in 2 chance of drawing an odd number add those together.
13 out of 30 chance
Simplify if necessary, hope this helps
