Grade 8
Algebraic Concepts
Name______Answer Key_______
1
1) Determine which of the following is equivalent to ?
Circle all your responses. Show your work.
(53 )( 5−5 )
(53 )(5−5 ) = 53+ −5 = 5−2 =
(5−1 )( 5−1 )
1
25
(5−1 )(5−1 ) = 5−1+ −1 = 5−2 =
(5−3 )( 5)
(5−3 )(51 ) = 5−3+1 = 5−2 =
(5−2 )( 54 )
25
1
25
1
25
(5−2 )(54 ) = 5−2+4 = 52 = 25
2) Identify the equation of the line represented by the table to the
right.
A
B
C
D
y = –2x + 5
y = 2x – 5
y = 5x – 2
y = –5x – 2
3) Explain your reasoning.
The y-intercept is (0, -2). A constant rate of change exists between all pairs of numbers
−42−−17
−8−−3
=
−25
−5
=5
−17 − −2 −15
=
=5
−3
−3 − 0
Grade 8
28 − −2 30
=
=5
6
6−0
Algebraic Concepts
Name______Answer Key_______
Using the point slope formula 𝑦 − 𝑦1 = 𝑚(𝑥 − 𝑥1 ) with the slope (m) = 5 and the point (-8, 42)
y + 42 = 5 (x+8)
y = 5x -2
Using the slope-intercept formula
y = mx +b with the slope (m) =5 and the y-intercept (b) = (0,-2)
y = 5x -2
Grade 8
Algebraic Concepts
Scoring Guide
0
• Student does not
identify a
response or work
is not related to
question.
Part 1 – Math
1
• Student’s work
shows partial
understanding.
• Student identifies
1 or 2 correct
responses.
Name______Answer Key_______
2
• Student’s work
shows
understanding
• Student
identifies all
three correct
responses.
(53 )( 5−5 )
(5−1 )( 5−1 )
Part 2 – Math
Part 2 - Writing
• Student does not
respond or work
is not related to
question.
(5−3 )( 5)
• Student
responds, work
shows
understanding,
and the
response is
correct (C).
• Student’s work
shows partial
understanding.
(for example,
evidence suggests
slope is
attempted, but
incorrect)
• No or poorly
• Explanation is
• Explanation is
written
written well, but
well written
explanation.
math vocabulary is
using
used
appropriate
• Explanation does
inappropriately or
math vocabulary
not contain
math reasoning is
and reasoning.
appropriate math
not correct.
vocabulary and
math reasoning is
not correct.