Part (a)
Independent variable = age
Dependent variable = height
"depends on age" indicates that age is independent.
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Part (b)
Independent variable = amount of sleep
Dependent variable = mood
The key word is "determines". The stuff before this word is the independent variable which affects the dependent variable.
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Part (c)
Independent variable = time water has been running
dependent variable = amount of water in the tub
Time is usually the independent variable
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Part (d)
Independent variable = speed
dependent variable = distance from home
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Part (e)
Independent variable = amount of homework done
dependent variable = speed
This seems like an odd pairing of homework and speed. Could there be a typo? I noticed that part (f) is very similar
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Part (f)
Independent variable = amount of hw that is assigned
dependent variable = amount of homework done
Like with part (a), the stuff before "depends" is the dependent variable
Answer:
C
Step-by-step explanation:
x - 7 > -6
x > -6 + 7
x > 1
• We change the inequality sign if we multiply or divide a negative number from both sides. But since it’s positive and we added it we won’t change the inequality sign.
Answer:
x ≥ 7
Step-by-step explanation:
|x - 7| = x - 7
A. For each absolute, find the intervals
x - 7 ≥ 0 x - 7 < 0
x ≥ 7 x < 7
If x ≥ 7, |x - 7| = x - 7 > 0.
If x < 7, |x - 7| = x - 7 < 0. No solution.
B. Solve for x < 7
Rewrite |x - 7| = x - 7 as
+(x - 7) = x - 7
x - 7 = x - 7
-x + 14 = x
14 = 2x
x = 7
7 ≮7. No solution
C. Solve for x ≥ 7
Rewrite |x - 7| = x - 7 as
+(x - 7) = x - 7
x - 7 = x - 7
True for all x.
D. Merge overlapping intervals
No solution or x ≥ 7
⇒ x ≥ 7
The diagram below shows that the graphs of y = |x - 7| (blue) and of y = x - 7 (dashed red) coincide only when x ≥ 7.
J, K, and L are collinear
J is between K and L
LK = KJ + LJ
LK = 9x + 7
KJ = 2x - 3
LJ = 4x - 8
9x + 7 = (2x - 3) + (4x - 8)
9x + 7 = (2x + 4x) + (-3 - 8)
9x + 7 = 6x + -11
9x + 7 = 6x - 11
9x + 7 - 7 = 6x - 11 - 7
9x = 6x - 18
9x - 6x = 6x - 6x - 18
3x = -18
x = -6
∴ The value of x is -6
If the tax rate is 8%, we need to find 108% of the price, or 330 times 1.08, which is $356.4
