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1 vote
4= square root of (-6-2x) plus square root of (31-3x)

User Anoroah
by
6.3k points

1 Answer

4 votes
Step 1 :Isolate a square root on the left hand side : Original equation
4 = √-6-2x+√31-3x

Isolate
-√-6-2x = -4+√31-3x

Tidy up
√-6-2x = 4-√31-3x

Step 2 :Eliminate the radical on the left hand side : Raise both sides to the second power
(√-6-2x)2 = (4-√31-3x)2

After squaring
-6-2x = 31-3x+16-8√31-3x

Step 3 :Get remaining radical by itself : Current equation
-6-2x = 31-3x+16-8√31-3x

Isolate radical on the left hand side
8√31-3x = 6+2x+31-3x+16

Tidy up
8√31-3x = 53-x

Step 4 :Eliminate the radical on the left hand side : Raise both sides to the second power
(8√31-3x)2 = (53-x)2

After squaring
1984-192x = x2-106x+2809

Step 5 :Solve the quadratic equation : Rearranged equation
x2 + 86x + 825 = 0

This equation has two rational roots:
{x1, x2}={-11, -75}
Step 6 :Check that the first solution is correct : Original equation, root isolated, after tidy up
√-6-2x = 4-√31-3x

Plug in -11 for x
√-6-2•(-11) = 4-√31-3•(-11)

Simplify
√16 = -4
Solution does not check
4 ≠ -4
Step 7 :Check that the second solution is correct : Original equation, root isolated, after tidy up
√-6-2x = 4-√31-3x

Plug in -75 for x
√-6-2•(-75) = 4-√31-3•(-75)

Simplify
√144 = -12
Solution does not check
12 ≠ -12 Hopefully this helped You
User Dan Kilpatrick
by
7.0k points
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