Answer:
y = -2·(1/2)^x
Step-by-step explanation:
The ratio of one table entry to the one before is ...
(-2)/(-4) = 1/2
so this is the growth factor.
The multiplier is the value of y when x=0, which is -2. So, the equation is ...
y = (multiplier)·(growth factor)^x
y = -2·(1/2)^x
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This can also be written using a negative exponent:
y = -2·2^(-x)