what is an example of a negative number and a non-example of a negative number? plz this is for homework

The multiplicative property of equality states that for real numbers a, b, c, and d, if a = b and c = d, then ac = bd. true false

Hell . what are the solutions to `10x^2 - 38x - 8 = 0`? is this when i find the factors and use the numbers within the factors to determine the zeros? i hope that made sense lol

Given δjkl : δxyz, find x. a)10 b)12 c)16 d)20