For the linear function, y increases by a of 3 each time x increases by 1.
For the exponential function, y increases by a(n)
of 3.

The linear equation is:

y = 3*x

when x = 1

y = 3*1 = 3

when x = 2

y = 3*2 = 6

Then as x increases one unit, y increases 3 units.

Then the correct statement would be something like:

"For the linear function, y increases by a sum of 3 each time x increases 1"

The exponential function is:

y = 3^x

When x = 1

y = 3^1 = 3

When x = 2

y = 3^2 = 3*3

when x = 3

y = 3^3 = 3*3*3

So when x increases by 1, we multiply the previous value of y by 3.

Then the correct sentence is something like:

"For the exponential function, y increases by a factor of 3".