(6b)(b=7)

Solution for (6b)(b=7) equation:

(6b)(b=7)

We move all terms to the left:

(6b)(b-(7))=0

We multiply parentheses

6b^2-42b=0

a = 6; b = -42; c = 0;
Δ = b2-4ac
Δ = -422-4·6·0
Δ = 1764
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$b_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$b_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{1764}=42$
$b_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-42)-42}{2*6}=\frac{0}{12}
=0
$
$b_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-42)+42}{2*6}=\frac{84}{12}
=7
$