Respuesta :
we have
[tex]x^{2}-40=0[/tex]
Step 1
Adds [tex]40[/tex] to both sides of the equation
[tex]x^{2}-40+40=0+40[/tex]
[tex]x^{2}=40[/tex]
Step 2
Take the square root of both sides
[tex]\sqrt{x^{2}}= \sqrt{40}[/tex]
[tex]x=(+/-)\sqrt{40} \\x1=+\sqrt{40}=2\sqrt{10} \\ x2=-\sqrt{40}=-2\sqrt{10}[/tex]
therefore
the answer is
the first step in solving the quadratic equation is
Adds [tex]40[/tex] to both sides of the equation