SOLUTION: Solve the quadratic equation by factoring. {{{x^2=400}}} I am having a hard time figuring out this problem. Please help and show the steps involved.

Algebra ->  Quadratic Equations and Parabolas  -> Quadratic Equations Lessons  -> Quadratic Equation Lesson -> SOLUTION: Solve the quadratic equation by factoring. {{{x^2=400}}} I am having a hard time figuring out this problem. Please help and show the steps involved.       Log On


   

Question 88704: Solve the quadratic equation by factoring. x%5E2=400
I am having a hard time figuring out this problem. Please help and show the steps involved.
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
x%5E2=400

x%5E2-400=0 subtract 400 from both sides


Solved by pluggable solver: Factoring using the AC method (Factor by Grouping)


%5E2%2B0%2A-400 Start with the given expression.



400%28%281%2F400%29%2B1-1%29 Factor out the GCF 400.



Now let's try to factor the inner expression %281%2F400%29%2B1-1



---------------------------------------------------------------





%28x-20%29%28x%2B20%29=0

x-20=0 or x%2B20=0 Set each factor equal to zero

x=20 or x=-20 Solve for x