9514 1404 393
Answer:
Step-by-step explanation:
You have to realize that the absolute value function will change the sign of its argument only if that argument is negative.
108. |x -7| = x -7 . . . . . true for x-7≥0
x ≥ 7 . . . . makes the statement true
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1a. When m < 9, the value 6m is less than 54, so 6m-54 < 0. That means the absolute value function changes the sign of its argument:
54 -6m . . . . . simplified form for m < 9
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1b. |y -x| = y -x . . . when y > x, the argument of the absolute value is positive
Answer:
A book is worth $1 and a DVD is worth $12.
Step-by-step explanation:
The equations (2 unknowns and two equations, d is for a DVD and b is for a book):
For David: 3d+4b=40
For Anna: d+6b=18
Now multiply the second equation with -3 and add to the first equation:
3d+4b=40
−3d−18b=−54
Combined equation: −14b=−14 and b=1 (means that each book is worth $1).
Now for DVD price, use the second equation:
d=18−6 or d=12 (means that each DVD is worth $12).
A book is worth $1 and a DVD is worth $12.
Answer:
68 minutes, 1 mile every 8.5 minutes
Step-by-step explanation:
:)
