How do. Use the quadratic equation to solve this
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Four problems:

Problem 1:

3x - 2 = 2sqrt(x) + 8

3x - 10 = 2sqrt(x)

9x^2 - 60x + 100 = 4x

9x^2 - 64x + 100 = 0

x = (64 +- sqrt(4096 - 3600))/18

x = (64 +- sqrt(496))/18

x = (64 +- 4sqrt(31))/18

x = (32 +- 2sqrt(31))/9

x = (32 + 2sqrt(31))/9, (32 - 2sqrt(31))/9

.

Problem 2

-3x + 2 = 2sqrt(x) + 8

-3x - 6 = 2sqrt(x)

9x^2 + 36x  + 36 = 4x

9x^2 + 32x + 36 = 0

x = (-32 +- sqrt(1024 - 1296))/18

Can't do square root of a negative, so no solution.

.

Problem 3

3x - 2 = 2sqrt(x + 8)

9x^2 - 12x + 4 = 4(x+8)

9x^2 - 12x + 4 = 4x + 32

9x^2 - 16x - 28 = 0

x = (16 +- sqrt(256 + 36*28))/18

x = (16 +- sqrt(256 + 1008))/18

x = (16 +- sqrt(1264))/18

x = (16 +- 4sqrt(79))/18

x = (8 +- 2sqrt(79))/9

x = (8 + 2sqrt(79))/9, (8 - 2sqrt(79))/9

.

Problem 4:

-3x + 2 = 2sqrt(x+8)

9x^2 - 12x + 4 = 4(x+8)

9x^2 - 12x + 4 = 4x + 32

9x^2 - 16x - 28 = 0

same as Problem 3

x = (8 + 2sqrt(79))/9, (8 - 2sqrt(79))/9

.

Answer:

If you meant abs(3x-2) = 2sqrt(x) + 8 then the answer is:  x = (32 + 2sqrt(31))/9, (32 - 2sqrt(31))/9

If you meant abs(3x-2) = 2sqrt(x+8) then the answer is:  x = (8 + 2sqrt(79))/9, (8 - 2sqrt(79))/9
by Level 13 User (103k points)

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