Hello Brainiac
x² = 81
Take square root
x = +/-√81
x = 9 or x = -9
x² = -9
We can not do anything for this one.
Thus, No real solutions
x² = 20
Take square root
x = +/-√20
x = 2√5 or x = -2√5
3x² = 125
x² = 125/3
Take square root
x = +/- √125/3
x = 6.45 or x = -6.45
I hope that helps!