College homework: solve x^2 - 80 = 0

emdorsheimer

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I had never taken algebra in highschool so this is all new to me. I have to show the steps on how to get the answers.

Solve x^2 - 80 = 0

I have 40 as the answer. Is that right?
 
Nope. Sorry.

If this were the problem

2*x = 80

You have the right answer.

x^2 - 80 = 0

Is a different animal.

x^2 = 80

\(\displaystyle x\,=\,\sqrt{80}\,or\,x\,=\,-\sqrt{80}\)

Quite a bit different.
 
college homework help

thank you, but how did you get the answer you did. I have to show the steps of how you get the answer
 
Are you learning in a classroom, with a teacher/tutor?
 
I am doing online college to become a science or english teacher for k-3rd grades. I do not need algebra and have been struggling through this class for 7 weeks now looking for help like you all have here. I had no idea. I have a D in the course right now and have only two more assignments until my final. The course is nine weeks and it is almost over. so I need help to bring my grade up to at least a C and I will be happy. Thanks
 
Re: college homework help

emdorsheimer said:
thank you, but how did you get the answer you did. I have to show the steps of how you get the answer

That is your steps. Well you could ge deeper.......

Whenever you you have:\(\displaystyle \L \;x^2\,=\80\) whenever you take the square root of both sides:


\(\displaystyle \L \;\sqrt{x^2}\,=\,\sqrt{80}\)


It get rids (it's the inverse of squaring) of the square:\(\displaystyle \L \;x\,=\,\sqrt{80}\)
 
emdorsheimer said:
how did you get the answer you did.
The tutored showed the steps: Get the number on the opposite side from the squared bit, and take the square root.

Has this not been covered in class...?

Eliz.
 
Technically, one would more properly factor the expression and apply the zero property. If a*b = 0, then either a or b must be zero.

Has this been covered?
 
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