If a and b are real numbers which of the following statements are true. |a+b|=|a|+|b|
|a-b|=|a|-|b|
|ab|=|a|*|b|
-|a/b|=-a/b

Which approach to the theory-and-research cycle does the following sequence reflect: (1) specific observations suggest generalizations, (2) generalizations produce a tentative theory, (3) the theory is tested through the formation of hypotheses, and (4) hypotheses may provide suggestions for additional observations?

Which value would be a solution for x in the inequality 47-4x< 7

Liz had 140 pens and inna had 100 pens. after inna gave liz some pens, liz had 3 times as many pens as inna. how many pens did inna give liz?