G8

Copyright © Swun Math Grade 8 Unit 2 Lesson 6 C TE

Input/Model

(Teacher Presents)

Directions: Write each expression using positive exponents.

1. 2 ି^3

Solution:

Use the patterns from yesterday’s chart or today’s

review of reciprocals.

• 2 ିଵ is equivalent to ଵ 2


• 2 ି2is equivalent to ଵ 2 ⋅ଵ 2 =ଵସ= 2 ଵమ


• Therefore 2 ି3 is equivalent to

ଵ

2 ⋅

ଵ

2 ⋅

ଵ

2 =

ଵ

଼=

ଵ

23

Answer: 2 ଵ 3

ଵ

2 ష3

Solution:

• Identify that the denominator 2 ଵష3 can be rewritten
  using its inverse. ଵభ
  మ^3


• The fraction bar also represents a division.
  Rewrite as a division problem.
  1
  ଵ
  23

= 1 ÷

1

23

• Lastly, simplify by multiplying by its reciprocal:
  1 · 23
  Answer: 23