This section explores how changes in b affect the exponential equation y = abx.
Exponential Equations
y = abx
Both exponential growth and exponential decay use the same equation, changes in the variable affect the graph of the function.
- Follow the link below.
- On the left, make sure c = 0 and a = 1.
- Move b.

Exponential Equations
This is a screenshot of the applet.

Source: Analyze Math, Exponential Functions
Example: Create an exponential function that has a y-intercept of 1 and where the y-values double for each x-value.

Answer the following in your notes.
Click on the blanks to reveal the answers.
- The exponential equation is Interactive button. Assistance may be required.
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y = 2x
, the y – value at x = 1 is Interactive button. Assistance may be required.
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2
.
- On the left, change the b to 3, the new equation is Interactive button. Assistance may be required.
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y = 3x
the y-value at x = 1 is Interactive button. Assistance may be required.
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3.
- Change b to 4, the new equation is Interactive button. Assistance may be required.
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y= 4x the y – value at x = 1 is
Interactive button. Assistance may be required.
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4.
- The graph Interactive button. Assistance may be required.
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increases faster as the base increases.
- Change b to 2, the new equation is Interactive button. Assistance may be required.
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y= 2x y – value x = 1 at is Interactive button. Assistance may be required.
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2.
- Change b to 0.5, the new equation is Interactive button. Assistance may be required.
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y= 0.5x y – value at x = 1 is Interactive button. Assistance may be required.
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0.5.
- When the b – value, or base, moves from 2 to 0.5, the graph changed from an exponential growth function to an Interactive button. Assistance may be required.
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exponential decay function, the base (b) is Interactive button. Assistance may be required.
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less than 1.