Math Unit 2 Test Flashcards
The graph of a quadratic is called a…
PARABOLA
The ? of a parabola is the point on the graph with the greatest y-coordinate if the graph opens down or the least y-coordinate if the graph opens up
VERTEX
When the quadratic relation is used to model a situation, the y-coordinate of the vertex corresponds to an ? (Maximum/Minimum) value.
OPTIMAL
Depending on the ? of the parabola, you will either have a ? or ? value of the equation
DIRECTION OF OPENING
MAXIMUM or MINIMUM
The ? value is always the y-value of the Vertex
MAXIMUM/MINIMUM
standard form + characteristics
y = a^2 + bx + c
- c is the y-intercept
- ‘a’ is positive it OPENS UP
- ‘a’ is negative it OPENS DOWN
vertex form + characteristics
y = a(x-h)^2 + k
- (h,K) is the VERTEX
- ‘a’ is positive it OPENS UP
- ‘a’ is negative it OPENS DOWN
factored form + characteristics
y = a(x-r)(x-s)
- ‘r’ and ‘s’ are the x-intercepts
- ‘a’ is positive it OPENS UP
- ‘a’ is negative it OPENS DOWN
Maximum if ‘a’ is …
NEGATIVE
Minimum if ‘a’ is …
POSITIVE
Maximum/Minimum Value is …
‘k’
Equation of Axis of Symmetry…
x = h
Steps to Completing the Square:
- Put brackets on the first 2 terms
- Factor out the value in front of x2
- Take ½ of the value in front of x and Square it
- Add AND Subtract that value into the bracket
- Remove the Subtracted value from the bracket, (multiply by ‘a’ when removing)
- Factor the trinomial bracket (it’s ALWAYS a Perfect Square Trinomial)
Revenue =
Cost x Number Sold
Area =
L X W
Steps for Real Life Applications of Quadratic Functions
- Create a let statement
- Ensure that there’s only one variable
- Sub that equation in
- Foil until you have a Quadratic Function
- Complete the square
- `Max/Min is K, X will be the ticket price or width
Solving a Quadratic Equations means to
find the unknown variable.
Steps to Solving Quadratic Equations by Factoring and Quadratic Formula
- Place all numbers and variables on one side of the equation = 0
- Strategies for solving Quadratic Equations
- Factoring
- Quadratic Formula
Quadratic Formula
x = -b +/- √ b^2 - 4ac / 2a
Vertex form - (h,k)
y = a(x-h)^2 + k
Factored form - x-intercepts r & s
y = a (x-r)(x-s)
My steps to Finding the Quadratic Equations
- Examine the question -
a. if you’re given a vertex (h,K) and a point (x,y) solve using vertex form
b. If you’re given the x-intercepts (r and s) and a point (x,y) solve using factored form - Sub everything else in
- Solve for a
- Rearrange the Equation
Nature of Roots =
How many Points of Intersection (x-intercepts) does the Quadratic Equation have?
Discriminant =
b^2 - 4ac