hey guys it's kaeleigh this lesson is on graphing
ordered pairs in the first quadrant let's get started
a coordinate grid is a grid where points are plotted coordinate grids have two or
more intersecting lines like these thick
black ones here that break the grid up into quadrants a quadrant
is a section on the grid this coordinate grid
has just one quadrant and it's called quadrant one
the origin is the place where the two thick lines
intersect or cross each other the coordinates at the origin
are zero 0.
the dark line that runs horizontally is called the x-axis
the dark line that runs vertically is called the
y-axis
an ordered pair is a list of two numbers in parentheses and separated by a comma
like this the ordered pair tells where a point is located on the
coordinate grid the first number is called the
x-coordinate and it responds to the x-axis
the second number is called the y-coordinate
it responds to the y-axis let's plot some ordered pairs
so here it looks like we have our ordered pair
five comma three so remember this first number here
responds to our x-axis and our second number responds to our y-axis
we have our x-axis down here and our y-axis
up here so to plot the c the ordered pair
five comma three we have to find five on the
x-axis to start so if i come down to my origin point here i'm going to move
5 on my x-axis that's right here and then i'm going to
move 3 on my y-axis so back at my origin
i go up to three now it's where those points
meet boom boom boom boom boom boom and
right here that's the point that's represented
by these coordinates so i can label it 5 comma 3.
nice work let's do another one so my coordinates this time is two comma
eight remembering the two responds to my x-axis and eight is my y-coordinate
responding to my y-axis so first let's find
our two on our x-axis i start at my origin
i move over 2 that's my x-coordinate my y-coordinate i start my origin i find
my 8 there's my y-coordinate so now the
point where these two points meet
is where my coordinate lives so my ordered pair
two comma eight lives right there now what if i have a 0 for my x
coordinate but i have a whole number 9 here for my y coordinate
so 0 on my x coordinate means from the origin i haven't moved
so my x-coordinate lives right there at zero
but my y-coordinate lives up here at nine on the y-axis
but because my x-coordinate is zero my actual point that my ordered pair
represents is right there on the y-axis
so this is the point 0 9 and notice
for every ordered pair that has a zero in the x coordinate spot that point will
live on our y-axis
now what do you think is going to happen when i have a 0 as my
y-coordinate but i have a whole number here a 7 for my x-coordinate
well let's find our x-coordinate on the x-axis so starting at the origin i go
over find my x-coordinate right there and then my y-coordinate is a 0
so i don't leave the origin so where these two points meet
is right here on the x axis that point seven zero that my ordered
pair tells me lives on the x axis
so just like the last problem anytime we have a zero in our y-coordinate
that point is going to live on the x-axis
let's try a different style of problem so now on this one i already have my
point here and what i need to find are my missing
coordinates so i know there's going to be a parenthesis
and a comma and this spot here is going to be my x coordinate
and this spot here will be my y-coordinate
so how am i going to find my x-coordinate if i have my point here
i know that my x-coordinate lives down here on the x-axis
so if i just make a little dashed line down here
it lives at the x coordinate 4. so i can put 4 in here
and now to find my y coordinate i know my y coordinate lives here on my
y so if i just draw a little line over here to my y-axis
it meets up at y-coordinate 5. so i can put that right there now i can
go ahead and label my point as 0.4 comma 5.
let's do one more like this so again here i have my point here but i'm
missing my ordered pair so i'm going to start
with my parentheses and my comma i know that this spot here
is going to be my x-coordinate and this spot here is going to be my y-coordinate
so remember my x-coordinate lives down here on the x-axis
let's go down and find it it falls right in line
with x-coordinate nine and to find my y-coordinate i have to
trace over here to my y-axis and it also falls on
coordinate nine
so i can go ahead and label my point with my ordered pair
nine comma nine great work now go ahead and practice
what you've learned by doing the online games and quizzes
have fun and remember to always be
clever