## Algebra

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### Algebra

by swerve » Thu Sep 24, 2020 1:35 pm

00:00

A

B

C

D

E

## Global Stats

If $$x$$ is positive and $$y$$ is $$1$$ more than the square of $$x$$, then what is the value of $$x$$ in terms of $$y$$?

A. $$y^2-1$$
B. $$y^2+1$$
C. $$\sqrt{y}-1$$
D. $$\sqrt{y-1}$$
E. $$\sqrt{y+1}$$

The OA is D

Source: Princeton Review

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### Re: Algebra

by psarma » Thu Sep 24, 2020 2:59 pm
Given y= $$x^2$$ + 1
So $$x^2$$ = y-1
x = $$\sqrt{y-1}$$

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### Re: Algebra

by [email protected] » Thu Oct 01, 2020 9:56 am
swerve wrote:
Thu Sep 24, 2020 1:35 pm
If $$x$$ is positive and $$y$$ is $$1$$ more than the square of $$x$$, then what is the value of $$x$$ in terms of $$y$$?

A. $$y^2-1$$
B. $$y^2+1$$
C. $$\sqrt{y}-1$$
D. $$\sqrt{y-1}$$
E. $$\sqrt{y+1}$$

The OA is D

Solution:

We are given that y = x^2 + 1. Thus:

x^2 = y - 1

x = ±√(y - 1)

However, since x is positive, then x = √(y - 1) only.