Question

ANSWER NOW PLEASE AND PLEASE GIVE ME THE RIGHT ANSWER 35 points

Find the difference. Express the answer in scientific notation.
Va
(8.64 x 1020)- (7 83x 1020)
O 8.1x 10
O 0.81 x 1020
O 8.1 x 1021
O 0.81x1040

Answer 1

B = 0.81 x 10^ 20

Explanation:

=(8.64 x 10^ 20)- (7 83x 10^20)

=8.1 x 10^19

which is also written as

= 0.81x 10^20

Answer 2

Both values have the same exponent ( they are both 10^20) so first subtract the numbers:

8.64 - 7.83 = 0.81

You would now have 0.81 x 10 ^20

But to be in scientific notation you need a number to the left of the decimal.

0.81 would become 8.1 and because you move the decimal 1 place to the left, you would subtract 1 from the original exponent so 10 ^20 would become 10 ^19

The answer is 8.1 x 10 ^ 19