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√4x-3 +√2x+3=6





pls answer its​

2 Answers

7 votes
Exact form x=69/8 decimal form x=8.625
Mixed number form x=8 with 5/8
User Murillo
by
5.4k points
2 votes

Answer:

X = 3

Explanation:

STEP 1: Isolate a square root on the left hand side

Original equation

√4x-3+√2x+3 = 6

Isolate

√4x-3 = -√2x+3+6

STEP 2: Eliminate the radical on the left hand side

Raise both sides to the second power

(√4x-3)2 = (-√2x+3+6)2

After squaring

4x-3 = 2x+3+36-12√2x+3

STEP 3: Get remaining radical by itself

Current equation

4x-3 = 2x+3+36-12√2x+3

Isolate radical on the left hand side

12√2x+3 = -4x+3+2x+3+36

Tidy up

12√2x+3 = -2x+42

STEP 4: Eliminate the radical on the left hand side

Raise both sides to the second power

(12√2x+3)2 = (-2x+42)2

After squaring

288x+432 = 4x2-168x+1764

STEP 5: Solve the quadratic equation

Rearranged equation

4x2 - 456x + 1332 = 0

This equation has two rational roots:

{x1, x2}={111, 3}

STEP 6: Check that the first solution is correct

Original equation, root isolated, after tidy up

√4x-3 = -√2x+3+6

Plug in 111 for x

√4•(111)-3 = -√2•(111)+3+6

Simplify

√441 = -9

Solution does not check

21 ≠ -9

STEP 7: Check that the second solution is correct

Original equation, root isolated, after tidy up

√4x-3 = -√2x+3+6

Plug in 3 for x

√4•(3)-3 = -√2•(3)+3+6

Simplify

√9 = 3

Solution checks !!

Solution is:

x = 3

User Amine El Were
by
3.7k points