Solve for x
x=2\sqrt{2}\approx 2.828427125
x=-2\sqrt{2}\approx -2.828427125
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x+3-\left(x+4\right)=\left(x-3\right)\left(x+3\right)
Variable x cannot be equal to any of the values -3,3 since division by zero is not defined. Multiply both sides of the equation by \left(x-3\right)\left(x+3\right), the least common multiple of x-3,x^{2}-9.
x+3-x-4=\left(x-3\right)\left(x+3\right)
To find the opposite of x+4, find the opposite of each term.
3-4=\left(x-3\right)\left(x+3\right)
Combine x and -x to get 0.
-1=\left(x-3\right)\left(x+3\right)
Subtract 4 from 3 to get -1.
-1=x^{2}-9
Consider \left(x-3\right)\left(x+3\right). Multiplication can be transformed into difference of squares using the rule: \left(a-b\right)\left(a+b\right)=a^{2}-b^{2}. Square 3.
x^{2}-9=-1
Swap sides so that all variable terms are on the left hand side.
x^{2}=-1+9
Add 9 to both sides.
x^{2}=8
Add -1 and 9 to get 8.
x=2\sqrt{2} x=-2\sqrt{2}
Take the square root of both sides of the equation.
x+3-\left(x+4\right)=\left(x-3\right)\left(x+3\right)
Variable x cannot be equal to any of the values -3,3 since division by zero is not defined. Multiply both sides of the equation by \left(x-3\right)\left(x+3\right), the least common multiple of x-3,x^{2}-9.
x+3-x-4=\left(x-3\right)\left(x+3\right)
To find the opposite of x+4, find the opposite of each term.
3-4=\left(x-3\right)\left(x+3\right)
Combine x and -x to get 0.
-1=\left(x-3\right)\left(x+3\right)
Subtract 4 from 3 to get -1.
-1=x^{2}-9
Consider \left(x-3\right)\left(x+3\right). Multiplication can be transformed into difference of squares using the rule: \left(a-b\right)\left(a+b\right)=a^{2}-b^{2}. Square 3.
x^{2}-9=-1
Swap sides so that all variable terms are on the left hand side.
x^{2}-9+1=0
Add 1 to both sides.
x^{2}-8=0
Add -9 and 1 to get -8.
x=\frac{0±\sqrt{0^{2}-4\left(-8\right)}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, 0 for b, and -8 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\left(-8\right)}}{2}
Square 0.
x=\frac{0±\sqrt{32}}{2}
Multiply -4 times -8.
x=\frac{0±4\sqrt{2}}{2}
Take the square root of 32.
x=2\sqrt{2}
Now solve the equation x=\frac{0±4\sqrt{2}}{2} when ± is plus.
x=-2\sqrt{2}
Now solve the equation x=\frac{0±4\sqrt{2}}{2} when ± is minus.
x=2\sqrt{2} x=-2\sqrt{2}
The equation is now solved.
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Simultaneous equation
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Limits
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