Question

When x increases from a to a + 2, y increases by a difference of 6. For which functions is this statement true?

A.y = 2(3)^x
B.y = 2(9)^x
C.y = 3x + 2
D.y = 9x + 2

Answer 1

C

Explanation:

USATestPrep

Answer 2

x2-x1 =a+2-a=2

y2-y1= 3x2 +2 -3x1 -2= 3(x2-x1)=3*2=6

correct answer is C

if D, then
y2-y1=9(x2-x1)=9*2=18, so D is wrong