Simplify the expression. write the answer using scientific notation. (5 x 10^7) (6 x 10^4)

The answer is 3.0×10¹².

(5×10⁷)(6×10⁴)
(5×6)(10⁷×10⁴)
30×10⁷⁺⁴
30×10¹¹

Since the constant cannot be greater than 10, move the decimal point to the left.
30×10¹¹
3.0×10¹¹

The decimal was moved by one space, so the constant must be multiplied by 10 the one power. The 10 to the eleventh power still needs to be multiplied as well.

3.0×10¹⁺¹¹
3.0×10¹²

Since two exponents with the same base are being multiplied, it can be simplified by adding the exponents. Therefore, the final answer is 3.0×10¹².

The second step on the test was the move he was supposed to