1. November 16, 2015
Today:
Make-Up Tests?
Absolute Value Test Results
New Khan Academy Topics
Warm-Up
Introduction to Literal Equations
Class Work 2.3
4. Formulas:
What are the two main temperature scales used in the world?
1. Fahrenheit 2. Celsius
F =
𝟗
𝟓
C + 32
If the temperature is 25o C, what is the temperature in
Fahrenheit? The formula is:
What is 24o C in Fahrenheit?
What if we know the temperature is 77o F. How do we
rearrange the formula to solve for C?
77
C = (F – 32)•
𝟓
𝟗
Finally, what is the temperature in Celsius if the
Fahrenheit temp is 50o? C = 10o
5.
6. T or F? Why or why not: | 2 −x | = | x − 2 |
Warm-Up/Review: (5)
4. What is one-half of
𝟑
𝟏𝟔
?
Mental Math!!
𝟕𝒛
𝟕
= 𝒛
7. Intro. to Literal Equations
The process of solving a formula for a given variable is
called "solving literal equations".
Solving literal equations is another way of saying
"take an equation with lots of variables, and solve
for one specific variable.”
To solve literal equations, you do what you've done all
along to solve equations, except that, due to all the
variables, you won't necessarily be able to simplify your
answers as much as you're used to doing.
Your answer might be something like:
p = 2Q + 14
Y
8. Solving with no Variables
1. Solve 40 = 66 + 14 for 14
2
a. Multiply each side by 2:
b. Subtract 16 from both sides
3m = 2k + n
c. 14 = 80 -66
Let’s start by doing exactly what we’re going to do,
except without variables
2. Solve 40 = 66 + 14 for 66
2
9. Solving for a Variable
1. Solve 3m - n = k: for m
2
a. Multiply each side by 2:
3m - n = 2k
b. Add n to each side:
3m = 2k + n
c. Divide each side by 3:
m = 2k + n
3
Whatever variable is being solved for must be
isolated on one side of the equation
2. Solve for y; 4x – 5y = 7
10. Class Notes:
Tips for Solving Literal & Other Equations:
1. If the variable you are solving for is inside the
parenthesis, you must distribute first. 9p = 3(k + 5) for k
2. If the variable you are solving for is outside the
parenthesis, simply perform the opposite operation.
9 = k(p + 5) for k
3. When clearing fractions, if the denominator being
multiplied has two or more terms, it must be distributed on
the other side.
5k(2p + 4) = 9
𝟓𝒌
𝟑
=
𝟑
𝟐𝒑+𝟒
for p
Literal Equations:
We need to separate the ‘k’ from the 5 in this case.
Solve the equation.
11. Literal Equations
Solve for y: 3y – 2(x + 1) = y + 3(x + 6)
Find the base of a triangle with an area of
49 in. and a height of 14 in.A = 49
b
14
One of the tsunami’s generated by the Indonesian earthquake
of 2004 travelled 11,000 miles and reached the shores of South
America 20 hours later. What was the average rate of speed for
the tsunami?
12. Light leaves the Sun travelling at 186,000 miles per second.
(The speed of light). It takes 8 minutes and 20 seconds for
the photons, the atoms of light, to reach Earth.
Literal Equations
The perimeter of a rectangle is 80 ft.2 The length is 25. Find
the width of the rectangle.
8 min. = 480 sec. + 20 = 500 sec. 500 ● 186,000 =93,000,000 miles
The formula is: p = 2l + 2w
Rearrange the formula to solve for w: w = p – 2l
2The width is 15
13. Class Work 2.3:
Due Wednesday, November 18th.
P.S.
Class Work is only credited
when submitted with work showing.
