ShmoopTube

Where Monty Python meets your 10th grade teacher.

Search Thousands of Shmoop Videos


TSI Mathematics Videos 144 videos

TSI Math: Writing the Slope-Intercept Equation of a Graphed Line
97 Views

What is the equation of the line graphed above?

TSI Math: Plugging in Slope and Point to Find the Equation of a Line
12 Views

A line passes through the point (-4, -4) and has a slope of . What is its equation?

TSI Math: Using Intercepts to Find the Slope of a Line
5 Views

Line A has an x-intercept of -4 and a y-intercept of 8. What is its slope?

See All

TSI Math: Factoring Trinomials 20 Views


Share It!


Description:

Factor completely.
9n2 + 15n + 4


Transcript

00:03

Okay sy match members Another bossy directive here Factor completely

00:12

What's the equation nine and squared plus fifteen in plus

00:15

fours and notice all these air special numbers No prime

00:19

numbers here so we'll probably be able to do some

00:21

factor in here All right Well there's one in every

00:23

crowd the prankster tricks You're the one who finds plastic

00:26

vomit hilarious on this test the jokester is the expression

00:29

nine in squared plus fifteen in plus four Why Well

00:32

the first and last terms are perfect squares So this

00:35

try No mia leads us to believe it's A perfect

00:37

square Trying amelia makes it easier to factor Check for

00:41

hand buzzers before grabbing onto this form to be a

00:43

perfect square Trying no menial the middle term must be

00:46

twice the product of the square root of the end

00:50

terms In other words it should be two times quantity

00:53

three times two right there equals twelve in So fifteen

00:57

in does not equal twelve ends of the cord Erratic

00:59

isn't actually a perfect square Try no meal Very funny

01:03

So well we could get rid of a immediately Well

01:05

ignore the jokes here A math joke Sorry It's A

01:08

lower standards and treat The expression is just a normal

01:10

expression while to factor a try no meal who's leading

01:13

coefficient isn't one So you gotta find factors of well

01:17

nine times for equal Thirty six And somehow these have

01:20

tto add two fifteen which is the coefficient in the

01:23

middle term Well what those factors while three times twelve

01:26

is thirty six and three plus twelve is fifteen So

01:30

rewrite fifteen n as three n plus twelve in and

01:34

no joke they have the same value so the replacement

01:36

is completely allowable See how that works So that gives

01:39

us nine squared plus fifteen in plus four is our

01:42

starting point Then we've got nine in squared plus three

01:45

and plus twelve in plus for group The first two

01:47

terms in the last two terms and factory g c

01:50

f out of the group and it looks like this

01:52

Nine in squared plus three and that quantity plus twelve

01:55

in plus four So then we got three and pulled

01:58

out here and they got three and plus one plus

02:00

for three in plus one Well the two term share

02:03

of greatest common factor of three and plus one there

02:05

and just factored out from both terms like any other

02:08

G c f and that gets us three end times

02:10

Quantity three and plus one plus four times quantity three

02:13

plus one and that boils down to three and plus

02:16

one times quantity three and plus for the correct factory

02:19

ization then is the quantity Three in plus one times

02:22

quantity three and plus ford and that's it We're done 00:02:25.575 --> [endTime] it See that's the right answer See you later

Related Videos

TSI Writing: Revising a Letter by Adding Transitions
147 Views

Which is the best way to revise and combine sentences 1 and 2?

TSI Writing: Adding a New Sentence to Improve a Letter's Structure
27 Views

Where would the following sentence best be placed?

TSI Writing: Choosing the Best Introductory Transition
18 Views

Which of the following is best to insert at the beginning of sentence 8?

TSI Writing: Shifting a Letter's Structure to Improve the Organzational Flow
8 Views

Which is the best location for sentence 9?

TSI Writing: Choosing the Most Effective Sentence Structure
15 Views

Which of the following sentences is best to insert between sentences 11 and 12?