Square Root Help..?

Question

12). 5 √(3-7x) = -2

14) √2x-2 - √x+6=1

15) √x+ √3= √x+3

Answer 1

12). 5 √(3 - 7x) = - 2
√(3 - 7x) = - 2/5
3 - 7x = 4/25
7x = 3 - 4/25
x = 71/175

14) √(2x - 2) - √(x + 6) = 1
2x - 2 - 2√(2x - 2)(x + 6) + x + 6 = 1
2√(2x - 2)(x + 6) = 3x + 3
4(2x^2 + 10x - 12) = 9x^2 + 18x + 9
8x^2 + 40x - 48 = 9x^2 + 18x + 9
x^2 - 22x + 57 = 0
x^2 - 22x + 121 = 64
(x - 11)^2 = ± 8
x = 3, 19

15) √x + √3 = √(x + 3)
x + 2√3x + 3 = x + 3
x = 0

Answer 2

I will do one.

This is called radical equations.

We have:

5 √(3-7x) = -2

Your goal is to isolate the radical.

Divide both sides by 5.

We get this:

√(3-7x) = -2/5

Next: Square both sides.

(√(3-7x))^2 = (-2/5)^2

3 - 7x = 4/25

Multiply both sides by 25 by every term to do away with the fraction on the right side of the equation.

25(3) - 7x(25) = 4

75 - 175x = 4

-175x = 4 - 75

-175x = -71

x = -71/-175

x = 71/175

Guido

Answer 3

1. square both sides

[5sqrt(3 - 7x)]^2 = (-2)^2
25(3 - 7x) = 4
75 - 175x = 4
-175x = -71
x = 71/175

Sorry, I cannot make out what the equations for 14 and 15 are suppose to be: what is under and what is not under the radical

Answer 4

15 is impossible where did u get these questions from?
12) is .4057

Answer 5

I'm sorry, I don't have a square for you, you'll have to find it yourself and when you do, please be discreet with it.