Question

(x - 5)^2 = 81

Which of the following expressions represents the solutions to the given equation?

Answer 1

a)-5 ± √(81)
b)5 ± √(81)
c)-25 ± √(81)

Answer 2

(x-5)^2 =81

root from (x-5)^2 = root from 81

|x-5|= 9

x-5= 9 or x-5= -9
x=14 x= -4


or you can solve this in this method:

(x-5)^2=81

x^2-10x+25-81=0
x^2-10x- 56=0

Delta= 100 -4*(-56) = 100+ 224= 324

x1;x2= (10 +/- 18)/2

x1= (10+18)/2= 28/2=14
x2=(10-18)/2= -8/2= -4

Answer 3

You've written the variants right?

Answer 4

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