ShmoopTube
Where Monty Python meets your 10th grade teacher.
Search Thousands of Shmoop Videos
Playlist GED Math: Expressions and Equations 14 videos
In this GED Math Equation, figure out how far Dmitri has travelled in his sleigh ride down the hill.
In this GED math equation, figure out if the given expression requires a greater than, less than or equal sign for completion.
GED Math 2.2 Expression and Equations. If a shirt is on sale for $12 then how much did it cost before the sale?
GED Math 3.4 Expression and Equations 311 Views
Share It!
Description:
GED Math: Expression and Equations Drill 3, Problem 4. What are the roots of the quadratic equation?
Transcript
- 00:00
Thank you We sneak in and here's your smoke to
- 00:05
your brought to you by the golden rule which is
- 00:08
basically don't ever try to take a leper con school
- 00:11
Really not worth getting away from my goal All right
- 00:14
one of the routes of the quadratic equation x squared
Full Transcript
- 00:16
plus seven x minus thirty equals forty eight and hear
- 00:19
the potential answers it is All right very matthew question
- 00:28
here We need to solve this quadratic x squared plus
- 00:32
seven x minus thirty equals forty eight and figure out
- 00:35
what the roots would be All right Well here's the
- 00:37
golden rule first solving quadratic always said one side of
- 00:40
the equation equal to zero before trying to factor well
- 00:44
to get one side to be zero We're going to
- 00:46
need to subtract forty eight from both sides and just
- 00:49
rewrite The equation is x squared plus seven x minus
- 00:51
seventy eight equals zero and now we need to get
- 00:55
two factors of negative seventy eight that add up to
- 00:57
seven Like what Times what would be seventy eight But
- 01:02
then if you also added to the seven and we
- 01:04
could start thinking well alright we think it could be
- 01:06
like thirty nine times to could it be three times
- 01:10
thirteen and no that's It can't break down thirteen any
- 01:15
further So the factors are two three and thirteen is
- 01:21
any combination of those make seven So the answer is
- 01:24
no not really But if we multiply the two and
- 01:27
the three together we get six and six from thirteen
- 01:32
is seven We need this To be negative seventy eight
- 01:35
So we'll have tohave one minus sign in there when
- 01:38
we're factoring and we're gonna wind up with x minus
- 01:41
six times x plus thirteen that if we multiplied check
- 01:46
ourselves except axes x squared than outside him outside his
- 01:50
x times thirteen thirteen x minus six x yeah thirteen
- 01:54
minus six is seven and then negative six times thirteen
- 01:57
Yep that gets us our negative seventy eight But now
- 02:00
that we're done factoring one of the routes well x
- 02:03
minus six zero so one factor has got to be
- 02:05
six and x plus thirteen's gotta be zero so yep
- 02:10
negative thirteen is the other one so our answers eh
- 02:14
You can have the answer but don't touch my gold
Related Videos
GED Math: Graphs and Functions Drill 5, Problem 5. What is the value of a?
GED Math: Measurement Drill 1, Problem 1. The area, in square inches, of the shaded region where the two rectangles overlap is...what?
GED Math 1.1 Graphs and Functions. Which is the appropriate region of the coordinate plane?
GED Math: Expression and Equations Drill 1, Problem 1. How much do the apples cost after tax?
