Aproportional relationship is a linear relationship because the rate of change is constant(and equal to the constant of proportionality).what is required of a proportional relationshipthat is not required of a general linear relationship

A proportional relationship is a relationship of two variables that are related by a constant of proportionality, this can be written as:

y = k*x

where k is the constant of proportionality.

While a linear equation has the form:

y = a*x + b

where a is the slope and b is the y-intercept.

you can see that the only difference is that in the case of the proportional relationship we do not have any y-intercept term, so the thing that is required in the proportionality relationship is that b = 0, while in a linear relationship b can take any value.

21

jk it's 20

step-by-step explanation:

-3.5 degrees per hour

step-by-step explanation:

find the unit rate:

-12   1/4 degrees           12.25 degrees

= - = -3.5 degrees per hour

      3   1/2 hours               3.5 hours