What is the equation for a circle?
(x-h)^2+(y-k)^2=r^2
What is the equation for a parabola?
(x-h)^2+(y-k)^2=(y-d)^2
What is our equation for a line?
(y-k)=m(x-h)
What number do you divide by 2?
Ex:
x^2+6x+"___"=4+"___"
(x+"___")^2="___"
you divide 6 by 2
How do you know if a transformation rule is congruent, similar, or neither?
(x,y)
No multiplication or division means Congruent
Mult/Divide by same # is Similar
Not same # is Neither
Write the equation for a circle given (2,4) and r=3
(x-2)^2+(y-4)^2=3^2
What is the definition of a parabola?
A group of points equally far away from the focus and directrix
How do you change the slope
5/3
to find perpendicular slope?
What is the parallel slope?
-3/5
"flip and change the sign"
5/3 " is parallel- same slope"
After completing the square, how do you find the center and radius?
(x-h)^2+(y-k)^2=r^2
so (h,k) is the center (change signs)
and its equal to r2, so
sqrt("what it's equal to")" gives the radius"
For the following transformation, state whether the transformation is congruent, similar or neither.
(-y,x)
Congruent
(No multiplication or division)
Write the equation for a circle given (-4,5) and r=2
(x+4)^2+(y-5)^2=2^2
Write the equation for a parabola given focus (4,2) and directrix y=6
(x-4)^2+(y-2)^2=(y-6)^2
Write the equation of a line parallel to
y=-3x+7
that goes through (2,4)
(y-4)=-3(x-2)
Find the center and radius of the circle
x^2+y^2-8x+2=4y
x^2-8x+"___"+y^2-4y+"___"=-2+"___"+"___"
(x+"___")^2+(y+"___")^2="___"
x^2+y^2-8x+2=4y
x^2-8x+"'16'"+y^2-4y+"'4'"=-2+"'16'"+"'4'"
(x+"'-4'")^2+(y+"'-2'")^2="'18'"
"center "(4,2) " and radius " sqrt(18)
For the following transformation, state whether the transformation is congruent, similar or neither.
(-2x,2y)
Similar
(Both multiplied by 2- negatives reflect so they have no effect on congruent vs similar because they don't change the size)
Is (1,-3) on the circle
(x-2)^2+(y+4)^2=3^2
No
(-1)^2+(1)^2=2!=9
Is (0,2) on the parabola
(x-4)^2+(y-2)^2=(y-6)^2
Ye
(0-4)^2+(2-2)^2=(2-6)^2
(-4)^2+0^2=(-4)^2
16=16
Label the equations as Parallel, Perpendicular, or Neither to the equation
y=3/5x-4
"a)" y-5=-3/5x+2
"b)" y+5/3x=7
a) neither
b)perpendicular
What is the center and radius of the circle?
x^2+y^2+2x-6y=6
(x+1)^2+(y-3)^2=16
Center (-1,3)
Radius 4
Do the transformation (x-5,y+3) on the figure


Is (2,-1) on the circle with center (2,-4) and r=3
"Yuh"
(x-2)^2+(y+4)^2=3^2
(2-2)^2+(-1+4)^2=3^2
(0)^2+(3)^2=3^2
9=9
Is (-8,0) on the parabola with focus (-3,1) and directrix y=5
Nah
(x+3)^{2}+(y-1)^{2}=(y-5)^{2}
(-8+3)^{2}+(0-1)^{2}=(0-5)^{2}
(-5)^2+(-1)^2=(-5)^2
26!=25
Write the equation of a line perpendicular to
y=2/3x-15
that goes through (-1,3)
(y-3)=-3/2(x+1)
What is the center and radius of the circle?
x^2-10y-4=-y^2-8x
(x+4)^2+(y-5)^2=45
Center (-4,5)
Radius
sqrt45 " or "6.71
Do the transformation (-y,x) on the figure

