use the square root property to solve this equation?

t^2 - 81 = 0

t^2 = 81

t = ± √81

t = ± 9

Check

QED

t^2 - 81 = 0 : original

Get variable on left and numbers on right :

t^2 = 81

Take the square root, remembering to use both positive and negative values :

t = ± 9

and that is the answer : 9 or -9

Both t^2 and 81 are perfect squares.

Since 81 is negative, the factors would not be identical.

(t + 9)(t - 9) = 0

t = -9

t = 9

Just remeber on these to find what two numbers equal 81 T=9

9*9 - 81=0

81- 81 = 0