(6x+1)5x+1=90

Solution for (6x+1)5x+1=90 equation:

(6x+1)5x+1=90

We move all terms to the left:

(6x+1)5x+1-(90)=0

We add all the numbers together, and all the variables

(6x+1)5x-89=0

We multiply parentheses

30x^2+5x-89=0

a = 30; b = 5; c = -89;
Δ = b2-4ac
Δ = 52-4·30·(-89)
Δ = 10705
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(5)-\sqrt{10705}}{2*30}=\frac{-5-\sqrt{10705}}{60}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(5)+\sqrt{10705}}{2*30}=\frac{-5+\sqrt{10705}}{60}
$