5t^2-8,49t-20=0

Solution for 5t^2-8,49t-20=0 equation:

5t^2-8.49t-20=0

a = 5; b = -8.49; c = -20;
Δ = b2-4ac
Δ = -8.492-4·5·(-20)
Δ = 472.0801
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{-(-8.49)-\sqrt{472.0801}}{2*5}=\frac{8.49-\sqrt{472.0801}}{10}
$
$t_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-8.49)+\sqrt{472.0801}}{2*5}=\frac{8.49+\sqrt{472.0801}}{10}
$