Good grief. More equations? Isolating the Variable in Literal Equations Notes for

Good grief. Good grief. More More

equations?equations?

Isolating the Variable in Isolating the Variable in Literal EquationsLiteral EquationsNotes for

Fetora strong, offensive

smell; a stench

SWBAT solve for a variable in a literal equation.

Literal EquationsLiteral Equations Just a whole bunch of letters!

Literal EquationsLiteral Equations An equation comprised only of variables!

That means it is all letters!!!

Only variables?! Only variables?! What does that What does that

mean?mean?

Literal EquationsLiteral Equations Literal equations is the fancy word for

formula

A formula is an algebraic expression relating two or more quantities For example:

The formula for area of a rectangle is A = bh The formula for the volume of a prism is V = Bh The formula for distance is d = rt

The Goal of Literal EquationsThe Goal of Literal Equations Isolate (solve for) a particular variable

This means that you must get everything on the right side of the equal sign except the variable you are solving for

Key Point:Key Point: By definition, variables represent numbers. Therefore (and this KEY), variables have the

same properties as numbers …

Variables can cancel each Variables can cancel each other out. I think that is other out. I think that is called inverse operations, called inverse operations,

right? Can we review right? Can we review those?those?

To cancel variable …To cancel variable … You must do the inverse (opposite) operation

So here we go …So here we go …

You guys are practicing? Huh, You guys are practicing? Huh, interesting. Perhaps I should try that. interesting. Perhaps I should try that. Because I don’t think that we have a Because I don’t think that we have a

team that will the west this year!team that will the west this year!

Solve for Solve for xx

53 x3533 x

2x

Now we will do the exact same thing …Now we will do the exact same thing …But with letters!But with letters!

Solve for a cba bcbba

bca

Get rid of the Get rid of the constant constant (subtract)(subtract)

Now let’s discussNow let’s discuss How were these two problems similar?

Solve for Solve for xx

64

x

46)4

(4 x

24x

Now we will do the exact same thing …Now we will do the exact same thing …But with letters!But with letters!

Solve for a

cb

a

bcb

ab )(

bca Get rid of the Get rid of the coefficient coefficient (multiply)(multiply)

Now let’s discussNow let’s discuss How were these two problems similar?

Solve for Solve for xx 305 x

5

30

5

5

x

6x

Now we will do the exact same thing …Now we will do the exact same thing …But with letters!But with letters!

Solve for b cab

a

c

a

ab

a

cb

Get rid of the Get rid of the coefficient coefficient (divide)(divide)

Now let’s discussNow let’s discuss How were these two problems similar?

Solve for Solve for xx 273 x72773 x

93 x

3

9

3

3

x

3x

Now we will do the exact same thing …Now we will do the exact same thing …But with letters!But with letters!

Solve for b dcab cdccab

cdab

a

cd

a

ab a

cdb

Start by Start by cancelling the cancelling the constantconstant

Now get rid ofNow get rid of

the coefficientthe coefficient

Now let’s discussNow let’s discuss How were these two problems similar?

Final ExampleFinal Example Solve for c bca 5

b

bc

b

a

5

5

5

b

ac

5

Remember, the coefficient is Remember, the coefficient is every term that is not the every term that is not the variable you are isolating!variable you are isolating!

Now go practice, because Now go practice, because this is probably the hardest this is probably the hardest

thing that you have ever thing that you have ever done. Kind of like trying to done. Kind of like trying to

beat my Vikings!!!beat my Vikings!!!

Practice makes PerfectPractice makes Perfect Solve for a

R + A = TR + A = T

Practice makes PerfectPractice makes Perfect Solve for a

Y – A = KY – A = K

Practice makes PerfectPractice makes Perfect Solve for A

1313LL = 5 = 5AA

Practice makes PerfectPractice makes Perfect Solve for m

7

mab

Practice makes PerfectPractice makes Perfect Solve for H

XH

P

Practice makes PerfectPractice makes Perfect Solve for m

MA + R = SMA + R = S

Practice makes PerfectPractice makes Perfect Solve for e

SLE – P = TSLE – P = T

Practice makes PerfectPractice makes Perfect Solve for o

dl

go

2

Practice makes PerfectPractice makes Perfect Solve for c

J = AC - KJ = AC - K

Practice makes PerfectPractice makes Perfect Solve for r

Z – E + BR = AZ – E + BR = A

Practice makes PerfectPractice makes Perfect Solve for k

sek

ca

Practice makes PerfectPractice makes Perfect Solve for e

T = EAT = EA

Practice makes PerfectPractice makes Perfect Solve for p

4

paw

Practice makes PerfectPractice makes Perfect Solve for a

CAB = SCAB = S

Practice makes PerfectPractice makes Perfect Solve for l

eugl 22

Practice makes PerfectPractice makes Perfect Solve for a

st

ac

Practice makes PerfectPractice makes Perfect Solve for g

sg

od

Practice makes PerfectPractice makes Perfect Solve for i

et

ki

Practice makes PerfectPractice makes Perfect Solve for p

ra

ep

Practice makes PerfectPractice makes Perfect Solve for a

kwa

h

Practice makes PerfectPractice makes Perfect Solve for a

na

f

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