Algebra Flashcards
Term
A term is a numerical constant or the product (or quotient) of a numerical constant and one or more variables
Variable
A letter used to represent a quantity whose value is unknown
Expression
An algebraic expression is a combinatiin of one or more terms.
Terms in an expression are separated by either addition or subtraction signs
Coefficient
In the term 3xy, 3 is called a coefficient.
In a single term, such as z, 1 is the coefficient
Constant
A value that does not change
Monomial
A single term
Polynomial
Expression with more than one term
Binomial
A polynomial with exactly two terms
Trinomial
A polynomial with exactly three terms
(a + b)^2
a^2 + 2ab + b^2
(a - b)^3
a^3 - 3a^2b + 3ab^2 - b^3
a^2 - b^2
(a + b)(a - b)
Quadratic formula
ax^2 + bx + c = 0
x = (-b +- sqrt(b^2 - 4ac))/2a
if the expression under the square root is 0, then there is only one solution, if negative there is no (real number) solution.
Domain of a function
the set of all permissible inputs
A mixture of 12 ounces of vinegar and oil is 40% vinegar. How many ounces of oil must be added to produce a mixture that is only 25%?
x = number of ounces of oil to be added
new mixture = 12 + x ounces
ounces of vinegar = 0.4 * 12 = 4.8
new mixture must be 25% vinegar, so:
amount vinegar / amount new mixture = 0.25
4.8 / (12 + x) = 0.25
4.8 = 3 + 0.25x
x = 1.8/0.25 = 7.2