5x2-7=488

Solution for 5x2-7=488 equation:

5x^2-7=488

We move all terms to the left:

5x^2-7-(488)=0

We add all the numbers together, and all the variables

5x^2-495=0

a = 5; b = 0; c = -495;
Δ = b2-4ac
Δ = 02-4·5·(-495)
Δ = 9900
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{9900}=\sqrt{900*11}=\sqrt{900}*\sqrt{11}=30\sqrt{11}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-30\sqrt{11}}{2*5}=\frac{0-30\sqrt{11}}{10}
=-\frac{30\sqrt{11}}{10}
=-3\sqrt{11}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+30\sqrt{11}}{2*5}=\frac{0+30\sqrt{11}}{10}
=\frac{30\sqrt{11}}{10}
=3\sqrt{11}
$