Answer: 8.1*10^(19)
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Step-by-step explanation:
Ignore the 10²⁰ portions. We can replace them with the variable m, or whatever letter you like
So the original expression becomes 8.64m - 7.83m which simplifies to 0.81m
Basically you subtract the values without the m, so 8.64-7.83 = 0.81
Then you tack on the m at the end.
The 0.81 itself is not in scientific notation, but we can fix that like so:
0.81 = 8.1*10^(-1)
Furthermore, we can say:
0.81m = 8.1*10^(-1)*m
0.81m = 8.1*10^(-1)*10^(20)
0.81m = 8.1*10^(-1+20)
0.81m = 8.1*10^(19)