Lourenço analyzed prices of laptop
computers based on the speed of the
processor. he calculated the trend line to
be y = 101x + 207.85, where x is the
speed of the processor in gigahertz and
y is the price. which amount below is
closest to the price of a laptop with a
processor speed of 2.5 gigahertz?
a. $309
b. $455
c. $460
d. $620
( show your work because i'm beyond confused

The price y is a function of x, the speed of the processor.

In function notation this means, y=f(x), where f(x)=101x + 207.85.

For example to calculate the (approximate) price of a laptop with processor 4 gigahertz, we let x=4, and plug in f. 

That is the price y for x=4 is calculated by y=f(4).

So, since y=f(x)=101x + 207.85, the (expected) price of a laptop with processor speed 2.5 gigahertz is :

y=f(2.5)=101(2.5)+207.85= 460.35 ($)

C. $460