Question

When x increases from a to a + 2, y increases by a difference of 8. For which functions is this statement true?

A) y = 2(4)^x
B) y = 2(8)^x
C) y = 4x + 2
D) y = 8x + 2

Answer 1

That would be Option C.

Explanation:

Lets look at y = 4x + 2:-

Let x = a then y = 4a + 2

Now if x in creases to a +2, y = 4(a +2) + 2 = 4a + 8 + 2

= 4a + 10.

(4a + 10) - (4a + 2) = 8 , so this is the required expression, y = 4x + 2.