Answer:
-63
Explanation:
sqrt(-49) = 7i
sqrt(-81) = 9i
7i × 9i
63i²
i is equal to √ -1
√ -49
√ 49 * √ -1
7*i
7i
√ -81
√ 81 * √ -1
9*i
9i
7i*9i
63i^2
i^2 equals -1
63*-1
3.4m questions
4.3m answers