Before solving the equation, we'll set the constraint of
existence of the sqrt.
2x + 5
>=0
2x>=-5
x>=-5/2
x+2>=0
x>=-2
2x-3>=0
2x>=3
x>=3/2
The
interval of admissible values for x is [3/2 , +inf.)
Now,
we'll solve the equation, raising to square both sides, in order to eliminate the square
root:
[sqrt(2x+5)]^2 = [sqrt(x+2) +
sqrt(2x-3)]^2
2x + 5 = x + 2 + 2x - 3 +
2sqrt(x+2)(2x-3)
We'll keep only the sqrt to the right
side, the rest of the terms we'll move them to the left
side:
2x + 5 -x - 2 - 2x + 3 =
2sqrt(x+2)(2x-3)
We'll eliminate like
terms:
6-x =
2sqrt(x+2)(2x-3)
We'll raise to square
again:
(6-x)^2 =
4*(x+2)(2x-3)
We'll expand the square and we'll remove the
brackets:
36 - 12x + x^2 = 8x^2 + 4x -
24
We'll move all terms to one
side:
36 - 12x + x^2 - 8x^2 - 4x + 24 =
0
We'll combine like
terms:
-7x^2 - 16x + 60 =
0
We'll multiply by -1:
7x^2 +
16x - 60 = 0
We'll apply the quadratic
formula:
x1 = (-16 + 44) /
14
x1 = 2
x2 = (-16 - 44) /
14
x2 = -60 / 14
x2 =
-30/7
Since the value of the first root
belongs to the interval of admissible values of x, the equation will have only one
solution, namely x = 2.
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