Transcript Solving Literal Equations

Solving Literal Equations
Text 3.8
So what is a literal equation and how do
you solve them?



follows the same rules as solving a linear
equation.
you are not solving for a specific value for x that
will make an equation true.
In a literal equation, you are simply rearranging
variables into a more convenient form so that
you can plug in values for variables later.
Formulas
 Literal
equations are usually formulas that
are used in some type of application. For
example,
area, force, volume, and distance formulas
can all be a starting point of a literal
equation.
Suppose you have the area
formula for a rectangle

When working with literal equations, you have to
be given an additional piece of information other
than simply being given a formula. You have to
be told what variable you will be solving for. The
way the equation is originally presented, we say
that the equation is solved for A.
A = lw
… In certain situations

it might be helpful to have the equation solved
for l.

this will involve the same skills needed to solve a
linear equation.

In this case, you only need to divide both sides
by w to have .
Solve for l:
A  lw
A
l
w
Divide both sides by w
or
A
l
w
As formulas become more
complicated
 it
is useful to have the equation solved for
a different variable
 so
you can go straight to plugging in
values that you know
 and
solving for the value you do not know.

Solve for l:

P=2(l+w)
P=2l+2w
P-2w=2l
P  2w
l
2
P
wl
2
 Solve
for h
bh
A
2
2 A  bh
2A
b
h
 Solve
for m
m
D
v
vD  m
 Solve
for t
d
r
t
tr  d
d
t
r

Solve for h
S  2rh
S
h
2r

Solve for y
3 y  6 x  12
 4 y  3x  16
3 y 6 x 12


3
3
3
 4 y 3 x 16


4 4 4
y  2x  4
3
y   x4
4

Solve for y
 2 x  y  15
+2x
+2x
y  2 x  15
5 x  y  3
-5x
-5x
y  5 x  3
Solve for y

2x+4y=8
4 y  2 x  8

4 y  2x 8


4
4
4
1x
y  2
2
2 y 2x 6


2
2 2
y  x3
-2x+2y=6
2 y  2x  6