Intercepts of Linear Equations - Concept

X and Y intercepts are extremely
important in your study of math.
Before you can get into a good depth of
algebra, you really need to understand
the ideas of X and Y intercepts and
how to find them both from a graph
and from an equation.


So what I have here is just
like a really rough graph.
I just drew a line up there.
There's no numbers or anything.
But what I wanted to show you is that when
you're looking at a graph, you can
find the Y intercept by looking on the
Y axis and seeing where your line
crosses it. That's the Y intercept.
And the X intercept is here. It's where your graph
crosses the X axis.
I'm using int to abbreviate for intercept.


When you think about the coordinates of
this, on your Y intercept, it's going
to be 0 for X, because I'm going 0
side to side and then I'm going up
some number Y. I don't know what
that number is on this particular
graph. But your Y intercept is always when
X is equal to 0. So if all you had
was an equation you would substitute
X equals 0 in order to find your
Y intercept.


Similarly, the value of the coordinates
of the X intercept are going to be some
X value comma 0 for Y. So if I have
an equation and I'm asked to
find the X intercept, I would plug
in Y equals 0.


Before I leave you guys, I want to tell you about one
of the tricks with intercepts is
remembering that to find the X intercept
you'll get Y equals 0. To
find the Y intercept you'll get X
equals 0. It's kind of tricky
but if you can keep it straight in your
head I think you'll do fine on
these problems.