(9j+7)(8j+5)=0

Solution for (9j+7)(8j+5)=0 equation:

(9j+7)(8j+5)=0

We multiply parentheses ..

(+72j^2+45j+56j+35)=0

We get rid of parentheses

72j^2+45j+56j+35=0

We add all the numbers together, and all the variables

72j^2+101j+35=0

a = 72; b = 101; c = +35;
Δ = b2-4ac
Δ = 1012-4·72·35
Δ = 121
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$j_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$j_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{121}=11$
$j_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(101)-11}{2*72}=\frac{-112}{144}
=-7/9
$
$j_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(101)+11}{2*72}=\frac{-90}{144}
=-5/8
$