Variables Though these systems have differences and unique properties, they share a common
trait: we can show the relationship graphically. Other than systems in algebra, what
other systems are in place in our wworld that are unique but share a common trait or
purpose?

last option

step-by-step explanation:

given that δdef is right and isoceles,

assuming that side df is the hypotenuse means that de an ef are the other 2 sides that intersect at 90° and are of equal length.

because they are of equal length, we can say that they are congruent

because they intersect at 90°, their slopes must be opposite reciprocals.

only the last option satisfies these conditions.

answer: you need to organize this better it does not make sense.

step-by-step explanation: ?

answer: 0

step-by-step explanation: the positive, like 5, + its opposite, like -5 would be 0

5+(-5)=0, or 5-5=0