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How to solve 3(x-4)^2=75 with the square root method

This is a quadratic. Please help, as I do not know the method for the a(x-p)^2=y form. Again, using the square root method.

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Peter H. | Tutoring in Math, Science, and Computer EngineeringTutoring in Math, Science, and Computer ...
Hi Sam,
With the square root method, we need to get the equation in the form of
    something squared = something else
and then take the square root of each side.
So, first let's divide each side of your equation by 3, to get
    (x-4)^2 = 25
Now we can take the square root of each side, and get
    (x-4) = 5  and  (x-4) = -5
Remember, 5*5=25, but also -5 * -5 = 25, so taking the square root gives us two solutions. Now we solve each of our equations
    (x-4) = 5 --> x = 9
    (x-4) = -5 --> x = -1
Our two answers are thus x=9 and x=-1. I leave it to you to insert these values back into the original equation and make sure I got it ok! Always double check your work.