Question

Subtract..

(8x^4+5x^3-6)-(2x^2-2x+6)

I got 8x^4+5x-2x^2+2x-12

convert the number to scientific notation.
19,450,000,000

I got 1.945x10^10

Answer 1

your first answer is right except the second term which should be 5x^3.

And writing in scientific notation, when moving decimal to left, exponent is negative, so correct answer will be 1.945*10^-10

Answer 2

I am sorry, your scientific notation is correct. When moving decimal to left exponent is positive.

Answer 3

1.945x10^10

or
1.945*10^-10

Answer 4

1.945*10^-10

or
1.945x10^10

Answer 5

1.945*10^-10

or
1.945x10^10

and 8x^4+5x^3-2x^2+2x-12
is this correct?

Answer 6

yes.

Answer 7

1.945*10^10 and yes your polynomial is correct.