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Math 084 –Algebra I
Spring 2014
Quiz 2 (total points: 10)
April 17, 2014
1. (1 pt) Solve:
3
17
𝑐−4= 4
Name: ____Anne Sers____________________
3
𝟑
𝑐−4+𝟒=
17
4
𝒄=
𝟏𝟕 𝟑
+
𝟒 𝟒
𝒄=
𝟐𝟎
𝟒
𝟑
+𝟒
𝒄=𝟓
2. (2 pts) Solve:
a) 8𝑢 − 9 = −2
b) 0 = 9(𝑏 + 8) − 12(𝑏 + 2)
8𝑢 − 9 + 𝟗 = −2 + 𝟗
0 = 9𝑏 + 72 − 12𝑏 − 24
8𝑢 = −7
8
𝑢=
𝟖
0 = −3𝑏 + 48
−7
3𝑏 = 48
𝟖
𝟕
𝟑𝒃
𝒖 = −𝟖
𝟑
=
𝟒𝟖
𝟑
𝒃 = 𝟏𝟔
3. (1 pt) What is the Addition Property of Equality?
One can add a term to both sides of an equation. The result is an equivalent equation; the solution is
unchanged.
4. (2 pts) Solve:
1
2
a) 2 (𝑥 + 9) + 3 (2𝑥 − 4) = 11
b) Check your answer from part “a”
1
Multiply both sides by 6
1
2
2
2
(𝟓 + 9) + (2 ∗ 𝟓 − 4) = 11
3
6 ∗ 2 (𝑥 + 9) + 6 ∗ 3 (2𝑥 − 4) = 11 ∗ 6
1
3(𝑥 + 9) + 4(2𝑥 − 4) = 66
3𝑥 + 27 + 8𝑥 − 16 = 66
11𝑥 + 11 = 66
11𝑥 = 66 − 11
11𝑥 = 55
11𝑥 55
=
11
11
x=5
7 + 4 = 11
2
2
(14) + 6 = 11
3
11 = 11 (𝒚𝒆𝒔, 𝒊𝒕 𝒄𝒉𝒆𝒄𝒌𝒔!)
5. (1 pt) Clear the fractions and solve: (multiply both sides by LCD: 12)
1
3
1
𝑐+ = 𝑐
6
4
2
1
3
1
12 ( 𝑐) + 12 ∗ = 12 ∗ 𝑐
6
4
2
2𝑐 + 9 = 6𝑐
2𝑐 − 2𝑐 + 9 = 6𝑐 − 2𝑐
9 = 4𝑐
9 4𝑐
=
4
4
𝟗
=𝒄
𝟒
6. (1 pt) Clear the decimals and solve: (multiply both sides by 100)
0.08𝑏 + 1 = 0.4
8𝑏 + 100 = 40
8𝑏 + 100 − 𝟏𝟎𝟎 = 40 − 𝟏𝟎𝟎
8𝑏 = −60
8𝑏 −60
=
8
8
𝟏𝟓
𝒃=−
𝟐
7. (1 pt)
Solve for C:
𝑅=
𝐸+𝐶
𝐿
RL = E +C
RL – E = C
8. (1 pt)
a) Solve the inequality
−2𝑥 + 12 > 16
b) represent the solution to “a” on
the number line
-2x + 12 -12 > 16 -12
-2x > 4
4
𝑥 < −2 (flip from > to < because dividing by a negative value)
x < -2