How do you solve #x^2-4=76#?

1 Answer
smendyka
Feb 13, 2017

See the entire solution process below:

Explanation:

First, add #color(red)(4)# to each side of the equation to isolate the #x^2# term while keeping the equation balanced:

#x^2 - 4 + color(red)(4) = 76 + color(red)(4)#

#x^2 - 0 = 80#

#x^2 = 80#

Now, take the square root of each side of the equation to solve for #x# while keeping the equation balanced. Remember, when taking the square root of a number there will be a negative and positive solution:

#sqrt(x^2) = +-sqrt(80)#

#x = +-sqrt(80) = +-8.944# rounded to the nearest thousandth

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