8.6=1.5t^2

Solution for 8.6=1.5t^2 equation:

8.6=1.5t^2

We move all terms to the left:

8.6-(1.5t^2)=0

We get rid of parentheses

-1.5t^2+8.6=0

a = -1.5; b = 0; c = +8.6;
Δ = b2-4ac
Δ = 02-4·(-1.5)·8.6
Δ = 51.6
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$t_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$t_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$t_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-\sqrt{51.6}}{2*-1.5}=\frac{0-\sqrt{51.6}}{-3}
=-\frac{\sqrt{}}{-3}
$
$t_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+\sqrt{51.6}}{2*-1.5}=\frac{0+\sqrt{51.6}}{-3}
=\frac{\sqrt{}}{-3}
$