Question

1. 3, 9, 27, 81...

Which exponential function describes the given sequence?
A) y=(-1/3)^x
B) y= 1/3^x
C) (-3)^x
D) y=3^x

2. Which sequence of y-values was formed from the function y = -2x - 9 using WHOLE numbers for x?
A) -13, -15, -17, -19
B) -13, -16, -19, -21
C) -11, -20, -29, -38
D) -10, -12, -14, -15

Answer 1

For the first one, notice that your terms are going up by powers of 3. This means your answer should be 3^x or (-3)^x. As they do not alternate between positive and negative, your answer will be 3^x, choice D. For the second one, note that it says whole numbers, meaning only values positive or 0. By pluggibg in 0, we see it gives -9. As we have a slope of -2, this means to get our next value we just subtract two. The answer choice that follows this pattern while staying odd, as our 0 was odd, is A.