Answer:
so you're going to need to find the slope. in order to do that use (y2-y1)/(x2-x1)
(7-(-2))/(0-8)
simplify
9/-8
simplify -9/8
now using y=mx+b, we need to find b. so we can plug in the coordinates of (0,7) or (8,-2). let's use (8,-2) because it involves more math.
y=mx+b
-2=(-9/8)(8)+b
multiply (-9/8) by 8 to get -9
-2=-9+b
add 9 to both sides
7=b
so our equation is now
y=-(9/8)x+7
Step-by-step explanation:
Its going up by 6, the answer is 33
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.
Step-by-step explanation:
In figure:
∠PRT+∠RTP+∠TPR=180
O
(angle sum property of triangle)
⇒x+(180
O
−∠RTQ)+60
O
=180
O
(linear pair)
⇒x+(180
O
−97
0
)+60
o
=180
O
⇒x=31
o
Now, ∠PRT+∠TRQ+∠QRS=180
O
(angle of straight line)
⇒x+48
o
+y=180
O
⇒31
o
+48
o
+y=180
O
⇒y=101
0
