The absolute value
returns the "positive version" of a number.
In other words, if the number is positive, it remains positive; if the number is negative, it changes sign.
So, if we want
, we want the "positive version" of x to be 9.
This can happen in two ways: if x is already 9, then its absolute value is still nine. If instead x=-9, its positive value will be 9 again.
In formula, we have

because

Correct answer: the first choice !
Answer:
Ellen bought 2700 paper clips.
Step-by-step explanation:
Total boxes=18
Paper Clips in 1 box=150
Total paper clips=18×150
=2700
Answer:
43.16 mg
Step-by-step explanation:
After each hour, the amount remaining is 100% - 12% = 0.88 times the amount present at the beginning of the hour. Then after 8 hours, the amount remaining will be the initial amount multiplied by 0.88 eight times, or ...
(120 mg)·(0.88^8) ≈ 43.1561 mg ≈ 43.16 mg
_____
Of course, an exponent is used to signify repeated multiplication. You can actually do the multiplication if you like, but most scientific and graphing calculators handle exponentiation easily.