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I need to know the solution of 4(x+3)-4=81/2x+1

2 Answers

7 votes

Answer:


x= (-7+√(697))/(8)


x= -(7+√(697))/(8)

Explanation:

4(x+3)-4 = 81/2x +1

Add 4 to both sides

4(x+3) = 81/2x +5

Multiply both sides by 2x (This removes the division from the second half)

8x(x+3) = 81 +10x

Simplify


8x^(2)+24x = 81 +10x

Subtract 10x from both sides


8x^(2) +14x = 81

Subract 81 from both sides


8x^(2) +14x -81 = 0

Solve using the quadratic formula


x= \frac{-b (+-) \sqrt{b^(2) -4ac}}{2a}

a= 8, b= 14, c= -81


x = \frac{-14 (+-) \sqrt{14^(2) -4 *8(-81)} }{2*8}

Simplify


\sqrt{14^(2) -4 *8(-81)} = 2√(967)


(-14 (+-) 2√(967))/(2*8)

Simplified Solution


x= (-7+√(697))/(8)

And


x=- (7+√(697))/(8)

I know this is confusing but I hope it helps. Keep in mind that (+-) means plus or minus. You might also look up what the quadratic formula is if you are not already familiar with it.

User Dienekes
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7 votes
What does x stand for?
User Muniro
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