3=4x-5
3+5=4x
8=4x
X=8/4=2
X=2 and Y=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.
Answer:
£63
Step-by-step explanation:
when we subtract 15 from 48 ,we get 63 which is the answer.
Make 2 eqn, let a be apples and o be oranges:
1. 5a + 4o = 10
2. 5a + 5o = 11
set up an elimination:
1. minus 2.
5a + 4o = 10
- 5a + 5o = 11
____________
o = 1
sub “o” into one of the eqn
5a + 5(1) = 11
5a = 11-5
5a = 6
a = 6/5
a = 1.2
therefore, an orange costs $1.00 and an apple costs $1.20
We know that the fence is 52 <em>feet</em> long, but since it's sold in yards, we need to somehow convert feet to yards.
First, we need to find a little something called a conversion factor. Basically, we need to see what we can do to get from <em>one foot</em> to <em>one yard</em>.
Well, how many feet are there in a yard? <em><u>3.</u></em><u /><u /> So now we know that <em><u>one foot is 1/3 of a yard.</u>
</em>
So to convert 52ft to yards, we need to divide by 3. What's 52 divided by 3?
17.33.
Now we just need to multiply that by 10.99 so that we can find out the cost.
We get 190.45. That's your answer!
It all cost <em>$190.45
</em>
<em>Don't forget to rate this answer the Brainliest!</em><em>
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