If x is positive and y is 1 less than the square of x, which of the fo

Question

If x is positive and y is 1 less than the square of x, which of the following expresses x in terms of y ?

(A)  x = y^2 - 1

(B)  x = y^2 + 1

(C)  x = \sqrt{y} + 1

(D)  x = \sqrt{1-y}

(E)  x= \sqrt{y+1}

pr3mk5 · Answer

Let X be X..

Y = X^2 - 1

Then X = \sqrt{Y+1}

OA -E

wardalaknaoui1 · Answer

Could you please explain how did you find that?

pr3mk5 · Answer

Given:

X is positive

Y = X^2 - 1

To Find:

X in terms of Y.

SOl:

we know that

y = X^2 - 1

taking 1 to the other side we get,

x^2 = y + 1

Now we take square root on both sides to get the value of X.

X = Sqrt(y+1)

we take only the positive value and not + or - sqrt(y+1) because it is given that X is positive.

So solution E.

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If x is positive and y is 1 less than the square of x, which of the fo

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If x is positive and y is 1 less than the square of x, which of the fo

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