Questions on Algebra: Quadratic Equation answered by real tutors!

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Question 154198: this is not in a text book
400(x-1)^2=225
this is what I have
400x^2-800x+175=0
my instructions are solve for x
x= -(-800) +/- sqrt[(-800)^2 - 4(400*175)]/2(400)
x= [800+/- sqrt(640000-280000)] / 800
x= (800 +/- sqrt 360,000) /800
x= (800 +/- 1.000000001)/800
is it right up to this point? where do we go from here?: this is not in a text book
400(x-1)^2=225
this is what I have
400x^2-800x+175=0
my instructions are solve for x
x= -(-800) +/- sqrt[(-800)^2 - 4(400*175)]/2(400)
x= [800+/- sqrt(640000-280000)] / 800
x= (800 +/- sqrt 360,000) /800
x= (800 +/- 1.000000001)/800
is it right up to this point? where do we go from here?
Answer by jim_thompson5910(9162) About Me  (Show Source):
You can put this solution on YOUR website!

400(x-1)^2=225 Start with the given equation.


(x-1)^2=(225)/(400) Divide both sides by 400.


(x-1)^2=9/16 Reduce.


x-1=0+-sqrt(9/16) Take the square root of both sides.


x-1=sqrt(9/16) or x-1=-sqrt(9/16) Break up the "plus/minus" to form two equations.


x-1=3/4 or x-1=-3/4 Take the square root of 9/16 to get 3/4.


x=1+3/4 or x=1-3/4 Add 1 to both sides.


x=7/4 or x=1/4 Combine like terms.


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Answer:


So the solutions are x=7/4 or x=1/4.