Solve for x
x=5
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\sqrt{5x-9}=\sqrt{x+4}-2+3
Subtract -3 from both sides of the equation.
\sqrt{5x-9}=\sqrt{x+4}+1
Add -2 and 3 to get 1.
\left(\sqrt{5x-9}\right)^{2}=\left(\sqrt{x+4}+1\right)^{2}
Square both sides of the equation.
5x-9=\left(\sqrt{x+4}+1\right)^{2}
Calculate \sqrt{5x-9} to the power of 2 and get 5x-9.
5x-9=\left(\sqrt{x+4}\right)^{2}+2\sqrt{x+4}+1
Use binomial theorem \left(a+b\right)^{2}=a^{2}+2ab+b^{2} to expand \left(\sqrt{x+4}+1\right)^{2}.
5x-9=x+4+2\sqrt{x+4}+1
Calculate \sqrt{x+4} to the power of 2 and get x+4.
5x-9=x+5+2\sqrt{x+4}
Add 4 and 1 to get 5.
5x-9-\left(x+5\right)=2\sqrt{x+4}
Subtract x+5 from both sides of the equation.
5x-9-x-5=2\sqrt{x+4}
To find the opposite of x+5, find the opposite of each term.
4x-9-5=2\sqrt{x+4}
Combine 5x and -x to get 4x.
4x-14=2\sqrt{x+4}
Subtract 5 from -9 to get -14.
\left(4x-14\right)^{2}=\left(2\sqrt{x+4}\right)^{2}
Square both sides of the equation.
16x^{2}-112x+196=\left(2\sqrt{x+4}\right)^{2}
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(4x-14\right)^{2}.
16x^{2}-112x+196=2^{2}\left(\sqrt{x+4}\right)^{2}
Expand \left(2\sqrt{x+4}\right)^{2}.
16x^{2}-112x+196=4\left(\sqrt{x+4}\right)^{2}
Calculate 2 to the power of 2 and get 4.
16x^{2}-112x+196=4\left(x+4\right)
Calculate \sqrt{x+4} to the power of 2 and get x+4.
16x^{2}-112x+196=4x+16
Use the distributive property to multiply 4 by x+4.
16x^{2}-112x+196-4x=16
Subtract 4x from both sides.
16x^{2}-116x+196=16
Combine -112x and -4x to get -116x.
16x^{2}-116x+196-16=0
Subtract 16 from both sides.
16x^{2}-116x+180=0
Subtract 16 from 196 to get 180.
x=\frac{-\left(-116\right)±\sqrt{\left(-116\right)^{2}-4\times 16\times 180}}{2\times 16}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 16 for a, -116 for b, and 180 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-116\right)±\sqrt{13456-4\times 16\times 180}}{2\times 16}
Square -116.
x=\frac{-\left(-116\right)±\sqrt{13456-64\times 180}}{2\times 16}
Multiply -4 times 16.
x=\frac{-\left(-116\right)±\sqrt{13456-11520}}{2\times 16}
Multiply -64 times 180.
x=\frac{-\left(-116\right)±\sqrt{1936}}{2\times 16}
Add 13456 to -11520.
x=\frac{-\left(-116\right)±44}{2\times 16}
Take the square root of 1936.
x=\frac{116±44}{2\times 16}
The opposite of -116 is 116.
x=\frac{116±44}{32}
Multiply 2 times 16.
x=\frac{160}{32}
Now solve the equation x=\frac{116±44}{32} when ± is plus. Add 116 to 44.
x=5
Divide 160 by 32.
x=\frac{72}{32}
Now solve the equation x=\frac{116±44}{32} when ± is minus. Subtract 44 from 116.
x=\frac{9}{4}
Reduce the fraction \frac{72}{32} to lowest terms by extracting and canceling out 8.
x=5 x=\frac{9}{4}
The equation is now solved.
\sqrt{5\times 5-9}-3=\sqrt{5+4}-2
Substitute 5 for x in the equation \sqrt{5x-9}-3=\sqrt{x+4}-2.
1=1
Simplify. The value x=5 satisfies the equation.
\sqrt{5\times \frac{9}{4}-9}-3=\sqrt{\frac{9}{4}+4}-2
Substitute \frac{9}{4} for x in the equation \sqrt{5x-9}-3=\sqrt{x+4}-2.
-\frac{3}{2}=\frac{1}{2}
Simplify. The value x=\frac{9}{4} does not satisfy the equation because the left and the right hand side have opposite signs.
\sqrt{5\times 5-9}-3=\sqrt{5+4}-2
Substitute 5 for x in the equation \sqrt{5x-9}-3=\sqrt{x+4}-2.
1=1
Simplify. The value x=5 satisfies the equation.
x=5
Equation \sqrt{5x-9}=\sqrt{x+4}+1 has a unique solution.
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Matrix
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Simultaneous equation
\left. \begin{cases} { 8x+2y = 46 } \\ { 7x+3y = 47 } \end{cases} \right.
Differentiation
\frac { d } { d x } \frac { ( 3 x ^ { 2 } - 2 ) } { ( x - 5 ) }
Integration
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Limits
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