Question

Did i do this right?

A coal car on a train weighs 30 tons plus 1 ton per cubic yard of coal x that it carries. The total weight of a coal car is: f(x) = x + 30. How will the graph of this function change if the coal car weight is changed to 26 tons?
The line will shift vertically up by 4 tons.
The line will shift vertically up 26 tons.
The line will shift vertically down by 4 tons.
The line will shift vertically down by 26 tons.

Answer 1

I chose C.

Answer 2

yes

Answer 3

ThaNks!

Answer 4

the new line would be
y = x + 26

this line has the same slope as the original (slope is 1)
but the y-intercept is 4 less than 30. So it will be a line parallel to the original but 4 steps below it.