ShmoopTube

Where Monty Python meets your 10th grade teacher.

Search Thousands of Shmoop Videos


Numbers and Operations Videos 63 videos

SAT Math 1.1 Numbers and Operations
280 Views

SAT Math 1.1 Numbers and Operations. How many combinations of beverage and cereal can be made?

SAT Math 1.2 Numbers and Operations
219 Views

SAT Math: Numbers and Operations Drill 1, Problem 2. If the masterpiece will be worth $45,055 in five years, what is its worth now?

SAT Math 1.3 Numbers and Operations
190 Views

SAT Math 1.3 Numbers and Operations. x and y must be which of the following?

See All

SAT Math: Solving a Rational Equation through Common Denominators 5 Views


Share It!


Description:

What are the value(s) of x in the rational equation above?


Transcript

00:00

Yeah Whoa Okay I say t mash bumpers and other

00:05

weird equation for you here We got this thing and

00:08

one of racks wanted Teo name exposed to what The

00:11

values of acts in the rational equation above All right

00:17

So rational meaning X is not zero nor negative too

00:20

Right Okay well let's think about this Would it be

00:22

irrational to a skip this rational equation question Probably because

00:27

it's much simpler than it looks Let's start by writing

00:29

every term with a common denominator because fractions loved to

00:32

get closer together So let's think about this We're going

00:35

to multiply out X plus two on both sides of

00:38

this thing and then x over exxon this thing and

00:41

then x over X I guess Yeah on this thing

00:43

So that gives us as the denominator extends quantity X

00:46

plus two and the numerator looks like this So then

00:49

we have What is that X plus two plus Acts

00:53

over X 20 exposed to and and that equals negative

00:56

two acts over this thing and then we can rewrite

00:58

it again as two x plus two over x ten

01:02

twenty flew and then equals negative to activate All right

01:05

so a few operations with fractions and our question becomes

01:08

so much easier to deal with The denominators of these

01:11

two fractions are exactly the same So the numerator Sze

01:13

must equal as well It's a big trick there You

01:16

have to know you crossed this whole bottom thing out

01:19

and it gives you two X plus two equals negative

01:21

to X Well then four Acts If you add 2

01:24

exit both sides and subtract two from their equals native

01:27

to so X is negative to force or negative one

01:31

half Well it's like he's our answer but because this

01:33

is a rational equation we need to check that B

01:36

is not an extraneous solution i e One that does

01:39

not make the denominator equal to zero We're looking at

01:42

the original equation We can see that if Acts were

01:44

equal 2:0 or negative too those would be extraneous Welby

01:48

doesn't cause any problems so well that's our answer You

01:51

got to be careful in these because they'll throw curveballs

01:53

like at you all day long If you divide by

01:55

zero it has to be undefined If it's not well 00:01:58.49 --> [endTime] it's probably wrong

Related Videos

Multiplying Polynomials to Find an Unknown Constant
3 Views

In the equation above, if a, b, and c are all constants, what is c?

Recognizing Polynomial Factors
4 Views

When x = 12, a certain polynomial, y, equals 0. Which of the following must be true about the polynomial y?

SAT Math 1.1 Algebra and Functions
315 Views

SAT Math 1.1 Algebra and Functions. Find an algebraic equation to correspond with the data.

SAT Math 1.1 Geometry and Measurement
719 Views

SAT Math 1.1 Geometry and Measurement. What is the circumference of the circle?

SAT Math 1.1 Numbers and Operations
280 Views

SAT Math 1.1 Numbers and Operations. How many combinations of beverage and cereal can be made?