T=-43t^2+7t

Solution for T=-43t^2+7t equation:

=-43T^2+7T

We move all terms to the left:

-(-43T^2+7T)=0

We get rid of parentheses

43T^2-7T=0

a = 43; b = -7; c = 0;
Δ = b2-4ac
Δ = -72-4·43·0
Δ = 49
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$T_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$T_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{49}=7$
$T_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-7)-7}{2*43}=\frac{0}{86}
=0
$
$T_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-7)+7}{2*43}=\frac{14}{86}
=7/43
$