Question

Slove this question c^2-81=0

Answer 1

To solve a square root, get the ^2 on one side and the 81 on the other side.
add 81 to both sides.

c^2 = 81
to clear the power of 2, take the square root of both sides.
c = + - sqrt81
c = + - 9
c = 9 and c = -9