Answer:
1. if y varies directly as x, and y = 6 when x = 2, the constant of variation is k = 6/2= 3. Thus, the equation describing this direct variation is y = 3x.
2. Partial Variation, where two variables are related by a formula, such as the formula for a straight line (with a non-zero y-intercept)
example :
in the milk factory Carol makes $10 per hour but gets an extra $20 from another job. since Carol gets a $20 allowance regardless of how much she works, if we want to represent Carol's situation in the form of an equation, it would be
Y=10x + 20
therefore if she worked zero hours
(Y=10(0) + 20),
she would still make $20 unconditionally and for every hour she works, she gets $10 more including the initial $20.
thus Carol's equation would be a partial variation, since her income doesn't entirely depend on how much she works.
3. a relation is non linear because it is has a direct relationship between an independent variable and a dependent variable.
In a relation, changes in the output do not change in direct proportion to changes in any of the inputs.
relations does not create a straight line but instead creates a curve.