2(5b^2-7b+2)=0

Solution for 2(5b^2-7b+2)=0 equation:

2(5b^2-7b+2)=0

We multiply parentheses

10b^2-14b+4=0

a = 10; b = -14; c = +4;
Δ = b2-4ac
Δ = -142-4·10·4
Δ = 36
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$b_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$b_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{36}=6$
$b_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-14)-6}{2*10}=\frac{8}{20}
=2/5
$
$b_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-14)+6}{2*10}=\frac{20}{20}
=1
$