What is the value of x?

Question

(1) 4x^2 - 4x + 1 = 0
(2) 4x^2 - 1 = 0

GMarc · Answer

There is a mistake in your question

I think it should be 1) 4x^2-4x + 1=0 shouldn't it ? With the new version the answer is indeed A otherwise there is no answer

sanjoo · Answer

yes .. its + sign.

Edited !

Bunuel · Answer

What is the value of x?

(1) 4x^2 - 4x + 1 = 0 --> recognize the square of the difference:  4x^2 - 4x + 1 = (2x-1)^2=0  -->  2x-1=0  -->  x=\frac{1}{2} . Sufficient.

(2) 4x^2 - 1 = 0 -->  x^2=\frac{1}{4}  -->  x=\frac{1}{2}  or  x=-\frac{1}{2} . Two different answers. Not sufficient.

Answer: A.

taransambi · Answer

What is the value of X?

1. 4.x^2-4.x+1=0
a=4, b=-4, and c=1. Use the quadratic formula: (-b +/- (Sqrt(b^2-4.a.c))/2a). Put the values and the discriminant, i.e. sqrt(b^2-4ac) becomes zero. This mean there is only 1 root which we don't have to calculate. SUFFICIENT

2. 4x^2-1=0
4x^2=1
x^2=(1/4)
x=sqrt(1/4)
x=1/2 OR -1/2 INSUFFICIENT

Therefore answer is A.

What is the value of x?

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