SOLUTION: how do you solve? 4x^2-16=0

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Question 144978This question is from textbook Elementary and Intermediate Algebra for College Students
: how do you solve?
4x^2-16=0 This question is from textbook Elementary and Intermediate Algebra for College Students

Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!

4x%5E2-16=0 Start with the given equation


4%28x%5E2-4%29=0 Factor out the GCF 4


4%28x%2B2%29%28x-2%29=0 Factor the left side using the difference of squares formula A%5E2-B%5E2=%28A%2BB%29%28A-B%29


Now set each factor equal to zero:

x%2B2=0 or x-2=0

x=-2 or x=2 Now solve for x in each case


So our answers are

x=-2 or x=2


Notice if we graph y=4x%5E2-16 we can see that the roots are x=-2 and x=2 . So this visually verifies our answer.


+graph%28500%2C500%2C-10%2C10%2C-10%2C10%2C0%2C+4x%5E2-16%29+