Solve the following quadratic function by utilizing the square root method. y = x2 - 64​

Solve The Following Quadratic Function By Utilizing The Square Root Method Y X2 64 class=

Sagot :

Answer:

[tex]x=\pm\sqrt{y+64}[/tex]

Step-by-step explanation:

All you need to do is isolate the x.

First, add 64 to both sides:

[tex]y=x^2-64\\x^2-64+64=y+64\\x^2=y+64[/tex]

Then, take the square root of both sides:

[tex]\sqrt{x^2}=\sqrt{y+64}\\x=\sqrt{y+64[/tex]

Actually, that is:

[tex]x=\pm\sqrt{y+64}[/tex]

Here's the reason for that. An example would be:

[tex]x^2=4[/tex]

Here, you'd take the square root of both sides to solve for x.

[tex]\sqrt{x^2}=\sqrt{4}\\x=2[/tex]

Right? But X could also be a -2, because a negative times a negative is a positive.

[tex](-2)^2=4\\-2\times-2=4\\4=4[/tex]

Therefore, [tex]x=2, -2[/tex] or [tex]x=\pm2[/tex]

[tex]x^2=2\times2=4\\x^2=-2\times-2=4[/tex]