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numbers and algebraic expressions
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elements of statistics
kropki game

Absolute value of any number is always positive or equals zero. Examples: |4| = 4, |-4| = 4, |0| = 0, |-5| = 5, |1/2| = 1/2. Geometric interpretation of the absolute value. Absolute value of a number is equal distance of this number from zero. Examples. Properties of the absolute value. |x| ≥ 0, |x * y| = |x| * |y|, |x/y| = |x|/|y|, |-x| = x, |x| = |y| ⇔ x = y or x = -y, |x+y| ≤ |x| + |y|, |x-y| = |y-x|.