If you vertically compress the linear parent function, f(x)=x, by multiplying by 1/2, what is the equation of the new function?

A function f(x) is said to be vertically compressed by a factor, a, when a < 1 and the resulting function is given by

y = a f(x)

Given the function, y = x, a vertical compression by a factor will result in the function

What are the following algebraic equations. you need to post those if you want the answer