SOLUTION: (2x-1)^2 = 9 Solve for x. Do I expand the brackets?

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Question 1037140: (2x-1)^2 = 9
Solve for x.
Do I expand the brackets?
Found 3 solutions by josgarithmetic, MathTherapy, ikleyn:
Answer by josgarithmetic(39623) About Me  (Show Source):
You can put this solution on YOUR website!
No, but instead you use some understanding of the exponents.

LOOK HERE: %282x-1%29%5E2=3%5E2

What should you do about the exponent 2 on both sides?



---
sqrt%28%282x-1%29%5E2%29=sqrt%283%5E2%29
2x-1=0%2B-+3
2x=1%2B-+3
x=%281%2B-+3%29%2F2
system%28x=-1%2COR%2Cx=2%29

Answer by MathTherapy(10555) About Me  (Show Source):
You can put this solution on YOUR website!

(2x-1)^2 = 9
Solve for x.
Do I expand the brackets?
%282x+-+1%29%5E2+=+9

No, that'd be too much work!

%282x+-+1%29%5E2+=+3%5E2

2x - 1 = 3 ------- EXPONENTS are equal, and so are the BASES 

2x = 3 + 1

2x = 4

highlight_green%28matrix%281%2C3%2C+x+=+4%2F2%2C+or%2C+x+=+2%29%29

Answer by ikleyn(52835) About Me  (Show Source):
You can put this solution on YOUR website!
.
(2x-1)^2 = 9
Solve for x.
Do I expand the brackets?
~~~~~~~~~~~~~~~~~~~~~~~~~~~

The are two solutions: x = 2 and x = -1. 

(2x-1)^2 = 9 --->  2x-1 = +/-3  --->  x = 2  or/and  x = -1.