Question

What are the solutions to the equation x2 = 81?   A. 40.5 only   B. 40.5 and –40.5   C. 9 and –9   D. 9 only

Answer 1

$x^2=81\ then\ x=9\ and\ x=-9\\\\because:(-9)^2=81\ and\ 9^2=81$


$x^2=81\to x=-\sqrt{81}\ and\ x=\sqrt{81}\to x=-9\ and\ x=9$

Answer 2

Answer:

C. 9 and -9

Step-by-step explanation: