SOLUTION: [ solve by extracting the root: 3(2x+3)^2=45 ]

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Question 822492: [ solve by extracting the root: 3(2x+3)^2=45 ]
Found 2 solutions by stanbon, TimothyLamb:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
3(2x+3)^2=45
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(2x+3)^2 = 15
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2x+3 = sqrt(15) or 2x+3 = -sqrt(15)
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x = (sqrt(15)-3)/2 or x = (-sqrt(15)-3)/2
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Cheers,
Stan H.
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Answer by TimothyLamb(4379) About Me  (Show Source):
You can put this solution on YOUR website!
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3(2x + 3)^2 = 45
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put the quadratic equation into standard form:
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3(2x + 3)^2 = 45
(2x + 3)(2x + 3) = 45/3
4xx + 12x + 9 = 15
4xx + 12x - 6 = 0
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the above quadratic equation is in standard form, with a=4, b=12, and c=-6
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to solve the quadratic equation, by using the quadratic formula, copy and paste this:
4 12 -6
into this solver: https://sooeet.com/math/quadratic-equation-solver.php
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this quadratic has two real roots (the x-intercepts), which are:
x = 0.436491673
x = -3.43649167
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Solve and graph linear equations:
https://sooeet.com/math/linear-equation-solver.php
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Solve quadratic equations, quadratic formula:
https://sooeet.com/math/quadratic-formula-solver.php
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Solve systems of linear equations up to 6-equations 6-variables:
https://sooeet.com/math/system-of-linear-equations-solver.php