Variable

Equations

Systems of

equations

absolute Value

equations and

inequalities

systems of

inequalities

Matrix

operations

and Equations

**100**

**100**

**100**

**100**

**100**

**200**

**200**

**200**

**200**

**200**

**300**

**300**

**300**

**300**

**300**

**400**

**400**

**400**

**400**

**400**

**500**

**500**

**500**

**500**

**500**

Vocabulary Word:

- letters or other symbols that

represent unknown numbers

or values

Variables

100

500

A stadium has 57,000 seats. Seats sell for $21 in section A, $18 in Section B, and $15 in Section C. The number of seats in section A equals the total number of seats in Sections B and C. Suppose the stadium takes in $1,071,600 from each sold-out event. How many seats does each section hold?

Section

A

has

28,500

seats.

Section

B

has

15,200

seats.

Section

C

has

13,300

seats.

The recommended daily intake (RDI) of Vitamin C is

95 mg/day

.

However, since supplement needs tend to vary from person to person, the dosage may

vary by plus or minus 35 mg

.

Write an absolute value inequality to find the dosage range.

500

60 < x < 130

Write the inequality that represents the sentence,

“Eight less than a number is greater than 62.”

x - 8 > 62

100

When given a system of inequalities, it's usually best to, if possible, isolate which

variable

? Why?

Y - so that the inequality resembles the slope-intercept form, which makes graphing easier.

100

Solve the equation:

12 - 3(2w + 1) = 5w - 3(5 + w)

Write an algebraic expression that

models the word phrase:

"the sum of the product of a number x and 9, and 15"

You currently have $45 in your bank account. Each week you plan to deposit $4 from your allowance and $30 from your paycheck. How many weeks from now will you have $315 in your bank account?

let b equal the money in the

bank after w weeks:

b = 45 + (30 + 4)w

8 weeks

Notice that your balance after 7 weeks is $283, and after 8 weeks it’s $317.

Since you only deposit money once a week, there is $315 in your account only after 8 weeks.

A new outdoor recreation complex is being built in Wylie. The perimeter of the rectangular playing field is 256 yards. The length of the field is 7 yards less than double the width. What are the dimensions of the playing field?

l

= 2w - 7

w = 45, l = 83

Vocabulary:

in a 2x2 system, the

lines coincide

;

in a 3x3 system, the 3 planes intersect at a

line

.

a system that has

infinite solutions

100

200

300

400

500

A laboratory technician needs to make a 27-liter batch of a 40% acid solution. How can the laboratory technician combine a batch of an acid solution that is pure acid with another that is 10% to get the desired concentration?

9L of the pure acid

solution

and

18L of the 10% acid

solution

are needed to

produce

the

27L batch of a 40% acid

solution.

Solve the system using any method:

2x – 3y + 5z = 0

x + 3y + z = 12

4y - z = 11

(2, 3, 1)

Solve the system using any method.

5x + y = 16

y = 3x

(2, 6)

200

300

400

Vocabulary:

the magnitude of a quantity, irrespective of sign;

the distance of a quantity from zero.

Solve:

2|4x-22| = 12

x = 7, x = 4

Solve & graph

on a number line:

|x + 14| > 5

x < -19

or

x > -9

The "solution" of a system of inequalities is the region where ______________________________________.

all three individual solution regions

overlap

.

Use the graph to write a matching system of inequalities.

200

300

400

200

300

Write a system of inequalities to describe the shaded figure:

y < -x + 6

y < x + 6

y > -x – 6

y > x – 6

400

Graph the solution set of the system:

-2x - y > 8

y > -8

x > -2

500

Answer:

100

Vocabulary - fill in the blanks:

in an m n matrix, m and n are

called its ___________;

where

m = # of _____

and

n = # of _______

.

Dimensions

n = # of

columns

m = # of

rows

True or False?

Multiplication of matrices is

commutative.

i.e.

Is multiplying the matrices,

AxB

, necessarily the same as multiplying

BxA

?

FALSE

; multiplication of matrices is NOT commutative

i.e.

AxB

will not necessarily be the same answer as

BxA

.

a means row 2, column 3

a = 1

200

300

Write a system of equations from the matrix equation:

4x – 2y + 6z = 5

4x + 6y – 4z = 3

-3x + 6y + 7z = 4

400

AxB =

.

500

**Algebra Jeopardy**

P= 2

l

+ 2w

9x + 15

Consistent

&

Dependent

w = 3

y < -x

y > -8

Absolute Value

**ALGEBRA JEOPARDY**

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