How do you solve quadratic equations by the square root?

Question

anonymous · Answer

www.youtube.com/watch?v=CAcpn-JjWrk

anonymous · Answer

that should help

hero · Answer

To receive proper help, please post the specific problem you are working on.

anonymous · Answer

(2x + 5)^2 = 49
Is the problem Im working on,
I took a look at that video earlier & its all still confusing. :/

hero · Answer

`1.` Square root both sides
`2.` Solve for x

`1.` $\sqrt{(2x + 5)^2} = \sqrt{49}$
        $\sqrt{(2x + 5)^2} = \sqrt{7^2}$

(Remember that square and square root are inverses of each other, so they cancel):

`2.` $2x + 5 = 7$


I'm pretty sure you can finish solving that on your own.

anonymous · Answer

How do I square root the first side?

hero · Answer

You just simply write a square root symbol above the right side, then tell yourself that square root and square cancel, then cancel them out. 

On the other side, you say to yourself 49 = 7^2. thus the square root of 7^2 = 7 since square root and square cancel as well. Pretty simple.

hero · Answer

Are you going to finish solving for x?

hero · Answer

I'd like to know what you get.

anonymous · Answer

Sorry I have a slow internet connection, its just equals 1?

anonymous · Answer

Yep! you got it! i did the work. so its definately right :) good job! :)

anonymous · Answer

Thanks for the help.!