5t(7-t)=0

Solution for 5t(7-t)=0 equation:

5t(7-t)=0

We add all the numbers together, and all the variables

5t(-1t+7)=0

We multiply parentheses

-5t^2+35t=0

a = -5; b = 35; c = 0;
Δ = b2-4ac
Δ = 352-4·(-5)·0
Δ = 1225
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$t_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$t_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{1225}=35$
$t_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(35)-35}{2*-5}=\frac{-70}{-10}
=+7
$
$t_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(35)+35}{2*-5}=\frac{0}{-10}
=0
$