Exponential decay formula is :
Where a≠0, b≠1 , b represent growth or decay factor (or rate) and x is any real number.
But if a radioactive isotope decays in half every year which means the decay factor or decay rate is 50% or
.
So, the formula for half decay will be:

Where
represent c) The rate of isotope decreases.
Answer:
x = 9
Step-by-step explanation:
81/9=9
Answer:
16
Step-by-step explanation:
Answer:
2/3 = a/b
Step-by-step explanation:
6/9 = a/b
2/3 = a/b
So, in this equation you're just plugging in I'm pretty sure. So x is -2 which is pretty self explanatory.. & y is 2. If you plug them in like so, your answer will turn out to be -6.
6(-2)+3(2)=-6
-12+6=-6
The answer should be -6 not -9.. so that was most likely a typo I'm pretty sure because the answer would not be correct as -9.