I am confused about the following problem, and cannot figure out how to solve it without using a graphing calculator.

Sqrt(x+5) - Sqrt(2x+3) = -2

How does one solve such a problem?

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- Nov 29th 2012, 03:15 PMyewchungHelp with Polynomials and Radicals
I am confused about the following problem, and cannot figure out how to solve it without using a graphing calculator.

Sqrt(x+5) - Sqrt(2x+3) = -2

How does one solve such a problem? - Nov 29th 2012, 04:18 PMzhandeleRe: Help with Polynomials and Radicals
Square both sides. You'll still have a radical on the LHS. Move everything but the radical term to the RHS, then square again. Should work.

- Nov 29th 2012, 04:39 PMyewchungRe: Help with Polynomials and Radicals
Ah. Thanks much.

- Nov 29th 2012, 04:47 PMzhandeleRe: Help with Polynomials and Radicals
What answer did you get?

- Nov 29th 2012, 06:21 PMSorobanRe: Help with Polynomials and Radicals
Hello, yewchung!

I tried the problem and got clumsy answers, but they checked out.

(Well, one of them checked . . . the other was extraneous.)

Quote:

Isolate a radical: .

Square both sides: .

n . . . . . . . . . . . . . . . . .

Isolate the radical: . . . . .

Square both sides: . . .

n . . . . . . . . . . .

n . . . . . . . . . . .

n . . . . . . . . . . .

Quadratic Formula: .

The only root is: .

- Nov 29th 2012, 06:32 PMyewchungRe: Help with Polynomials and Radicals
Thank you very much.

Knowing my teacher, that clumsy number is probably the right one.