Practice with Exponential
Equations and Graphs
Topic Index | Algebra Index | Regents Exam Prep Center

 


Investigate these equations for exponential growth and decay.
(You may want to use your graphing calculator for checking.)
 

1.

Given ,  evaluate y when x = 3.

Choose:

3
9
27

 

 

2.

 Given ,  evaluate y when x = -2.

Choose:

-9
-1/9 
 1/9

 

 

3.

 Would the graph of show exponential growth or exponential decay?  

Choose:

growth
decay  

 

 

4.

 Would the graph of show exponential growth or exponential decay?  

Choose:

growth
decay 

 

 

 

5.

The equation will be an exponential function when a equals ______.

Choose:

-1
  0
 1
  2

 

 

6.

Which ordered pair represents the y-intercept for the function ?

Choose:

(0,0) 
(0,1)
(0,2)



 

7.

 The graph of lies in which Quadrants?

Choose:

I, II
I, III
I, IV 

 

 

8.

The graph of contains which of these points?

Choose:

(0,0)
(0,1)
(0,2) 

 

 

9.

 Which graph below depicts ?  

Choose:

a
b
c
d
a b
c d

 

 

10.

 A piece of paper is folded in half so that there are two thicknesses (or layers) of paper.  These new layers are folded in half again to form 4 layers.  If this folding continues, which equation will best represent the number of layers of paper (y), in terms of the number of folds (x), where x is a whole number? 

Choose:


  

 

 

11.

An important characteristic of exponential decay is the time required for the decaying quantity to fall to one half of its initial value.  This time is called the half-life.  A radioactive substance decays exponentially with a half-life of 500 years.  After 1,500 years, what percent of the radioactive material remains?

Choose:

30%
15%
12.5%