A direct variation is a relationship between 2 variables in which the changes are proportionate. The variables are related by a constant. This is also called a slope. Thus, the graph would always be a straight line. Therefore,
c) Direct variation models are always a type of linear models
a) The straight line always pass through the origin(0, 0)
b) A polynomial is an expression containing variables and coefficients. The variable can be in the form x^n where n can be any positive integer. This means that n can be 1,2,3,4.....If n is 1, the polynomial expression is linear. Thus, it can be a direct variation model. Therefore,
Direct variation models are sometimes a type of polynomial models
d) An exponential model is not linear. The form of a linear model is
y = ax
where a is the constant of pro
An exponential model is y = ab^x
The models are not the same. Thus,
Direct variation models are never a type of exponential model