Algebra Flashcards
Strategy Guide II
Many problems with two or more inequalities can be combined…
- What must inequalities have to be combined
– What is the process?
- What do you do if variables do not combine?
One common term to align
- Simplify
- Ensure signs point the same way
- Stack
*Note: inequalities w/ multiple variables may not combine, if so:
A) combine what you can
B) Find common term through multiplying or dividing
Inequalities (Compare QTY’s w/ different values)
- Translating Graph Formula
- Dividing or Multiplying inequality by a negative
- | x - midpoint | ≤ distance from end to mid point
–– shaded = included / equal to
–– open = excluded / more or less than - diving or multiplying inequality by a negative…flip the sign!!
What to consider?
AV | means two end solutions, both not always valid!
Two scenarios and plug extreme values into x
Scenario #1: (positive) = positive
Scenario #2: (positive) = (negative)
The most difficult Q’s involve multiple brackets on one side….you must test numbers (try strat guide Q #15)
- Exponents & Roots…how are they related?
- Even Exponents…why are they significant?
Opposite equations, which cancel one another out.
ie: a square cancels a square root (vice versa)
ie: cube root cancels out cube exponent
Solve for x under radical:
Isolate & multiply or divide by corresponding exponent
Solve for variable with an exponent:
Isolate, take corresponding root on both sides
Root of a term with EVEN exponent always results in the AV of that term.
Quadratic Equations (variables to 1st & 2nd power)…how do you solve?
– Factor to solve
– Ensure x^2 term is positive
– Set #’s equal to zero
It is possible for a quadratic to have only one solution.
– Given as quadratic, consider factoring
–– Given with factors, consider FOILING
–––If factors already set to zero…DO NOT FOIL…instead set each factor equal to zero
Hidden Quadratics
ax^2 + bx + c = 0
Discriminat = b^2 - 4ac
Quadratic Formulas (3)
- ) x² – y² = (x-y)(x+y)
- ). x² + 2xy + y² = (x+y)²
- ) x² – 2xy + y² = (x-y)²
Quadratic Inequalities
Must be factored to be solved.
Multiple Equations (2)
1.) Stack and eliminate (only works when addition or subtraction can cause one to cancel out thus must have opposite coefficients.
- ) Isolate and substitute.
- - Isolate opposite of ask to solve
Three or more equations can use either or both! Substitution often easiest.
Multiple Equations with Addition or Subtraction and Multiplication =
Quadratics
Plugging addition or subtraction eq into multiplication eq produces a quadratic
eg) x + y = 20 and xy = 64
plugging x = 20- y into xy = 64 gives you a Quadratic
Inequalities & Equations combined…what do you do?
Isolate variable in common
Substitute the equation into the inequality