Math 8 Unit 1

Vocabulary

100

to make easier or less complicated

simplify

200

a statement that shows how 2 things are equal

equation

300

a symbol that has a fixed numerical value

constant

400

a symbol whose value is not fixed

variable

500

a mathematical phrase with no equal sign

expression

One Step Equations

100

x-4=6

10

200

14+y=25

11

300

12/x = 6

2

400

4x=64

16

500

1/3x = 15

45

Two Step Equations

100

5z+2 = 12

2

200

3z - 12 = 3

5

300

8 = 14x - 90

7

400

2y + 4 = 5

1/2

500

7x - 12 = 37

7

Solve for y

100

8x - 2y = 10

y = -5 + 4x

200

7 = -y + 3x

y = 3x - 7 (OR -7 + 3x)

300

A = bh

Solve for h.

h = A/b

400

2x + 4y = 11

y = -1/2x + 11/4

500

1/3x + y = 4

y = 4 - 1/3x

Potpourri

100

d=rt

Solve for r.

r = d/t

200

4x + 0 = 0

x = 0

300

What is the P in PEMDAS?

parentheses

400

-14 + -65 = x

x = -79

500

1/8x = 15 + -1/7x

x = 56

Variable on both sides

100

2(x+4) = -5x + 1

x = -1

200

1/2s = 4s-21

s = 6

300

8.3z = 4.1z + 10.5

z = 2.5

400

3(b+5) = 4(2b-5)

b = 7

500

-2(x - 5) = 6(2 - 1/2x)

x = 2

One, None, or Infinite?

100

x + 2 = x + 7

no solution

200

x + 2 = x + 2

infinite solutions

300

3x - 5 = 7 + 3x

no solution

400

x^{2 =} 25

2 solutions (5 and -5)

500

6x + 4 = 4(3/2x + 1)

infinite solutions