Solve for x
x=3
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\left(2x\right)^{2}=\left(\sqrt{4x+24}\right)^{2}
Square both sides of the equation.
2^{2}x^{2}=\left(\sqrt{4x+24}\right)^{2}
Expand \left(2x\right)^{2}.
4x^{2}=\left(\sqrt{4x+24}\right)^{2}
Calculate 2 to the power of 2 and get 4.
4x^{2}=4x+24
Calculate \sqrt{4x+24} to the power of 2 and get 4x+24.
4x^{2}-4x=24
Subtract 4x from both sides.
4x^{2}-4x-24=0
Subtract 24 from both sides.
x^{2}-x-6=0
Divide both sides by 4.
a+b=-1 ab=1\left(-6\right)=-6
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as x^{2}+ax+bx-6. To find a and b, set up a system to be solved.
1,-6 2,-3
Since ab is negative, a and b have the opposite signs. Since a+b is negative, the negative number has greater absolute value than the positive. List all such integer pairs that give product -6.
1-6=-5 2-3=-1
Calculate the sum for each pair.
a=-3 b=2
The solution is the pair that gives sum -1.
\left(x^{2}-3x\right)+\left(2x-6\right)
Rewrite x^{2}-x-6 as \left(x^{2}-3x\right)+\left(2x-6\right).
x\left(x-3\right)+2\left(x-3\right)
Factor out x in the first and 2 in the second group.
\left(x-3\right)\left(x+2\right)
Factor out common term x-3 by using distributive property.
x=3 x=-2
To find equation solutions, solve x-3=0 and x+2=0.
2\times 3=\sqrt{4\times 3+24}
Substitute 3 for x in the equation 2x=\sqrt{4x+24}.
6=6
Simplify. The value x=3 satisfies the equation.
2\left(-2\right)=\sqrt{4\left(-2\right)+24}
Substitute -2 for x in the equation 2x=\sqrt{4x+24}.
-4=4
Simplify. The value x=-2 does not satisfy the equation because the left and the right hand side have opposite signs.
x=3
Equation 2x=\sqrt{4x+24} has a unique solution.
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Simultaneous equation
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Differentiation
\frac { d } { d x } \frac { ( 3 x ^ { 2 } - 2 ) } { ( x - 5 ) }
Integration
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Limits
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