Test 1 Flashcards
zero factor property
factor and equal zero
root property
+-square root of other side
complete the square
- Move constant to other side
- add 1/2 b squared to both sides
- (x+1/2b)^2=constant on other side
- root property
complete the square with number in front of x^2
- Move constant
- factor out a
- complete the square
- remember to add xa to other side
- divide by a
- root property
MFCDR
quadratic formula
-b+- square root b^2-4ac / 2a
whenever you take the square root
+-
Discriminants
- number/type of solution
- found using b^2-4ac
Positive, perfect square discriminant
- 2 solutions
- rational number
positive, not perfect square discriminant
- 2 solutions
- irrational number
zero discriminant
- 1 solution
- rational number
negative discriminant
- 2 solutions
- imaginary/complex number
Distance formula
d= square root (x2-x1)^2 + (y2-y1)^2
are the points of the triangle the vertices of a right triangle?
- use distance formula
- a^2+b^2=c^2
- can also use slope- should be perpendicular (= -1)
are the points collinear?
- on the same line
- d(AB)+d(BC)=d(AC)
midpoint formula
(x1+x2/2 , y1+y2/2)
y int
x=0, solve for y
x int
y=0, solve for x
general form of the equation of a circle
ax^2+by^2+cx+dy+e=0
circle with center (h,k) and radius r has the equation
(x-h)^2 + (y-k)^2=r^2
three possibilities for the graph of a circle given the center-radius form
(x-h)^2 + (y-k)^2=m
- if m is greater than 0, then r^2=m and the graph is a cycle with the radius square root m
- if m=0, then the graph is a single point (h,k)
- if m is less than 0, then no points satisfy the equation and the graph is non existent
show that (long equation) has a circle as its graph
- use complete the square to put it in center-radius form
- m greater than 0
The set of x-values are called the
domain
the set of y-values are called the
range