(x-7)(x+7)=49

Solution for (x-7)(x+7)=49 equation:

(x-7)(x+7)=49

We move all terms to the left:

(x-7)(x+7)-(49)=0

We use the square of the difference formula

x^2-49-49=0

We add all the numbers together, and all the variables

x^2-98=0

a = 1; b = 0; c = -98;
Δ = b2-4ac
Δ = 02-4·1·(-98)
Δ = 392
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:

$\sqrt{\Delta}=\sqrt{392}=\sqrt{196*2}=\sqrt{196}*\sqrt{2}=14\sqrt{2}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-14\sqrt{2}}{2*1}=\frac{0-14\sqrt{2}}{2}
=-\frac{14\sqrt{2}}{2}
=-7\sqrt{2}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+14\sqrt{2}}{2*1}=\frac{0+14\sqrt{2}}{2}
=\frac{14\sqrt{2}}{2}
=7\sqrt{2}
$