2. Definition
A solution of an equation is
a number or numbers that
when substituted for the
variable in the equation
produces a true statement.
Two equations are
equivalent equations if they
have the same solutions.
3. Important Idea
Graphical solutions to
equations provide an
approximate solution when
algebraic methods are not
available to find an exact
solution.
5. Definition
To solve an equation of the
form by using the
intersection method:
( ) ( )f x g x=
1) Graph and1 ( )y f x=
2 ( )y g x= on the same screen.
2) Find the x coordinate of
each point of intersection.
12. Try This
Find the approximate
solutions to the following
equation using the intersect
method:
4 2
3 1 4x x x+ − + =
x = -1.65,
2.03
13. Definition
The solution(s) to an
equation set equal to zero
is called a zero or root of
the equation. The solutions
are where the function
crosses the x axis and
y=0.
14. Definition
The x-intercept method of
solving an equation requires
these 3 steps:
1) Write the equation in the
equivalent form ( ) 0f x =
2) Graph ( )y f x=
3) Use 2nd
CALC 2:Zero
18. Important Idea
The values that make the
numerator zero make the
fraction 0. There is no need
to find the values that make
the denominator zero; these
values make the fraction
undefined.
19. Lesson Close
In our next lesson, we will
study methods of solving
equations algebraically.