SOLUTION: a)SOLVE 2X^2=6 b) Find the x-intercepts of f(x)=2x^2-6 What are the solutions? What are the x-intercepts? Thank you for any help!!!!
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Question 155616
:
a)SOLVE 2X^2=6
b) Find the x-intercepts of f(x)=2x^2-6
What are the solutions?
What are the x-intercepts?
Thank you for any help!!!!
Answer by
jim_thompson5910(35256)
(
Show Source
):
You can
put this solution on YOUR website!
a)
Start with the given equation
Divide both sides by 2
or
Take the square root of both sides.
So the solutions are
or
which approximate to
or
==================================================
b)
Start with the given function
Plug in
Notice we have a quadratic equation in the form of
where
,
, and
Let's use the quadratic formula to solve for x
Start with the quadratic formula
Plug in
,
, and
Square
to get
.
Multiply
to get
Rewrite
as
Add
to
to get
Multiply
and
to get
.
Simplify the square root (note: If you need help with simplifying square roots, check out this
solver
)
Break up the fraction.
Reduce.
or
Break up the "plus/minus" to form two equations.
So the answers are
or
which approximate to
or
So this means that the x-intercepts are
and
which in decimal form are (1.732,0) and (-1.732,0)
======================================================
Notice how the solutions of the first equation are simply the x-coordinates of the x-intercepts.