x(2x+7)=490

Solution for x(2x+7)=490 equation:

x(2x+7)=490

We move all terms to the left:

x(2x+7)-(490)=0

We multiply parentheses

2x^2+7x-490=0

a = 2; b = 7; c = -490;
Δ = b2-4ac
Δ = 72-4·2·(-490)
Δ = 3969
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{3969}=63$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(7)-63}{2*2}=\frac{-70}{4}
=-17+1/2
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(7)+63}{2*2}=\frac{56}{4}
=14
$