7(x*x)+x-30=0

Solution for 7(x*x)+x-30=0 equation:

7(x*x)+x-30=0

We add all the numbers together, and all the variables

7(+x*x)+x-30=0

We add all the numbers together, and all the variables

x+7(+x*x)-30=0

We multiply parentheses

7x^2+x-30=0

a = 7; b = 1; c = -30;
Δ = b2-4ac
Δ = 12-4·7·(-30)
Δ = 841
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{841}=29$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(1)-29}{2*7}=\frac{-30}{14}
=-2+1/7
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(1)+29}{2*7}=\frac{28}{14}
=2
$