55 terms

# algebra formulas

slope and graphing (chapter 3)

#### Terms in this set (...)

When do you use point-slope form
when you have the slope and one set of points .................y-y1=m(x-x1)
what is a range
all y coordinates
what is a domain
all x coordinates
what does a 0 in the denominator mean
undefined
what is standard form?
Ax+By=C
what formula do I use when I need to determine if lines are parallel or perdendictular
slope intercept ...y=mx+b
what is the formula to determine the slope
m=y2-y1 / x2-x1
what is slope formula
m=y2-y1 /x2-x1
What is the formula to determine rate of change
slope formula m=y2-y1 / x2-x1
what is slope intercept formula
y=mx+b
in slope intercept what is the b?
the y intercept
what is the formula for point slope form
Y-Y1=M(X-X1)
what formula do you use when you have the slope and one set of points
point slope formula ...y-y1=m(x-x1)
when can you use slope intercept form
when you have points that include zero (0,#)
when a line is horizontal is has what slope
zero slope
when a line is vertical is has what slope
undefined (zero in denominator)
when do you use slope form
when you have 2 sets of points ....m=y2-y1 / x2-x1
all linear equations are functions except for those of the form what, which are vertical lines
x=c
what kind of line is x=2
vertical
function is another name for what
y
How do you use the vertical line test to determine if something is a function
if a vertical line can be drawn so that it intersects a graph more than once, the graph is not a function
what is a function
set of ordered pairs that assigns to each x value exactly one y value
is this a function? (-1,0),(-1,6),(-1,8)
no, because negative 1 is paired with 3 different y's
what formula do you use if you have the slope and one point
point slope form y-y1=m(x-x1)
what formula do you use if you only have 2 sets of points
use two formulas: m=y2y1 / x2-x1 to find slope then use.... y-y1=m(x-x1) and plug in one point and slope
when do you use point slope form
when you have a point and slope and your set of points doesn't have a zero in it. If it has a zero, use slope intercept form
how do you know if a line is perpendicular
if the product of a slope is -1
slope =
rise/run
what formula do you use when you have one point and the slope
point-slope form
standard form can't have what
a negative variable
what kind of line is y=3
horizontal
what kind of line is x=3
vertical
how do you change slope intercept to standard form in y=3x+2
move the x and y to the same side. = 3x-y=2
what formula is the same as counting the rise over the run
slope formula m=y2-y1 / x2-x1
when finding x intercepts...
let y =0 (cover up y)
when finding y intercepts...
let x -0 (cover up x)
when finding intercepts which one do you cover up?
the one that is 0
a vertical line has...
no y intercept
a horizonal line has...
no x intercept
y=3 is what kind of line
horizontal
when you are plotting intercept don't forget...
that intercepts need two #'s
what variable is always first in standard notation
x
what is an intercept
where x and y cross each other
what is a linear equation in two variables
one that can be written in the form as Ax+By=C
the graph of a linear equation in two variables is what
a straight line
the graph of m=yx+b crosses the y-axis at what
(0,b)
rise equals what
change in y
run equals what
change in x
parallel lines have the same what and different what
same slope, different y-intercepts
f(x) does not mean what
f times x
when subtracting negatives
if the signs are the same, you add and keep the sign
standard form means what
solve for y
how do you find slope if you don't have any points
use slope intersept form y=mx+b, the coefficent of x is the slope
How do you find the domain
the denominator needs to equal 0, input what will make the answer 0
how to you write interval notation to exclude a specific #.
(negative infinity, the specific #) u(the specific #, infinity)