Solving Exponential Equations
• One way to solve exponential
equations is to use the property that if
2 powers w/ the same base are equal,
then their exponents are equal.
• For b>0 & b≠1 if bx
= by
, then x=y
Exponential Equations
Solve by equating
exponents
Check →
3 3 9
2 2
x
 Since they have the same
bases we can set their
exponents equal to each
other and solve for x.
3 3 9
x  
4
x   
3 4 3 9
9 9
2 2
2 2



Your turn
Solve by equating exponents
3 1
4 8
x x
 Since they do NOT
have the same bases…
we have to rewrite so
they have common
bases.
Common base = 2
   
3 1
2 3
2 2
x x

6 3 3
2 2
x x

6 3 3
x x
 
1
x 
Check →
 
3 1 1 1
4 8
64 64



Distribute!
Your turn
Solve by equating exponents
3
1
4
2
x
x

 
 
  Common base = 2
   
3
2 1
2 2
x x


2 3
2 2
x x
 

2 3
x x
 
1
x 
Check →
1 3
1
2
2
1
4
2
1
4
2
4 2
4 4


 
 
 
 
 
 


How can we make ½ a
base of 2?
Negative exponents!!!
Distribute!
You Try
Your turn!
Be sure to check your answer!!!
2
9 3
x x

2
x 
Your turn!
Be sure to check your answer!!!
3
1
3 ( )
9
x x

2
x 
Your turn!
Be sure to check your answer!!!
4 4
9 27
x x


4
5
x 
Practice/H.W.
Solving Exponential Equations
WS

solving-exponential-equations-ppt-3.pptx

  • 1.
  • 2.
    • One wayto solve exponential equations is to use the property that if 2 powers w/ the same base are equal, then their exponents are equal. • For b>0 & b≠1 if bx = by , then x=y Exponential Equations
  • 3.
    Solve by equating exponents Check→ 3 3 9 2 2 x  Since they have the same bases we can set their exponents equal to each other and solve for x. 3 3 9 x   4 x    3 4 3 9 9 9 2 2 2 2   
  • 4.
  • 5.
    Solve by equatingexponents 3 1 4 8 x x  Since they do NOT have the same bases… we have to rewrite so they have common bases. Common base = 2     3 1 2 3 2 2 x x  6 3 3 2 2 x x  6 3 3 x x   1 x  Check →   3 1 1 1 4 8 64 64    Distribute!
  • 6.
  • 7.
    Solve by equatingexponents 3 1 4 2 x x        Common base = 2     3 2 1 2 2 x x   2 3 2 2 x x    2 3 x x   1 x  Check → 1 3 1 2 2 1 4 2 1 4 2 4 2 4 4                 How can we make ½ a base of 2? Negative exponents!!! Distribute!
  • 8.
  • 9.
    Your turn! Be sureto check your answer!!! 2 9 3 x x  2 x 
  • 10.
    Your turn! Be sureto check your answer!!! 3 1 3 ( ) 9 x x  2 x 
  • 11.
    Your turn! Be sureto check your answer!!! 4 4 9 27 x x   4 5 x 
  • 12.