Solve for x
x=\sqrt{10}\approx 3.16227766
x=-\sqrt{10}\approx -3.16227766
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\left(x+2\right)\times 5=x\left(x+2\right)+x\times 3
Variable x cannot be equal to any of the values -2,0 since division by zero is not defined. Multiply both sides of the equation by x\left(x+2\right), the least common multiple of x,x+2.
5x+10=x\left(x+2\right)+x\times 3
Use the distributive property to multiply x+2 by 5.
5x+10=x^{2}+2x+x\times 3
Use the distributive property to multiply x by x+2.
5x+10=x^{2}+5x
Combine 2x and x\times 3 to get 5x.
5x+10-x^{2}=5x
Subtract x^{2} from both sides.
5x+10-x^{2}-5x=0
Subtract 5x from both sides.
10-x^{2}=0
Combine 5x and -5x to get 0.
-x^{2}=-10
Subtract 10 from both sides. Anything subtracted from zero gives its negation.
x^{2}=\frac{-10}{-1}
Divide both sides by -1.
x^{2}=10
Fraction \frac{-10}{-1} can be simplified to 10 by removing the negative sign from both the numerator and the denominator.
x=\sqrt{10} x=-\sqrt{10}
Take the square root of both sides of the equation.
\left(x+2\right)\times 5=x\left(x+2\right)+x\times 3
Variable x cannot be equal to any of the values -2,0 since division by zero is not defined. Multiply both sides of the equation by x\left(x+2\right), the least common multiple of x,x+2.
5x+10=x\left(x+2\right)+x\times 3
Use the distributive property to multiply x+2 by 5.
5x+10=x^{2}+2x+x\times 3
Use the distributive property to multiply x by x+2.
5x+10=x^{2}+5x
Combine 2x and x\times 3 to get 5x.
5x+10-x^{2}=5x
Subtract x^{2} from both sides.
5x+10-x^{2}-5x=0
Subtract 5x from both sides.
10-x^{2}=0
Combine 5x and -5x to get 0.
-x^{2}+10=0
Quadratic equations like this one, with an x^{2} term but no x term, can still be solved using the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}, once they are put in standard form: ax^{2}+bx+c=0.
x=\frac{0±\sqrt{0^{2}-4\left(-1\right)\times 10}}{2\left(-1\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -1 for a, 0 for b, and 10 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\left(-1\right)\times 10}}{2\left(-1\right)}
Square 0.
x=\frac{0±\sqrt{4\times 10}}{2\left(-1\right)}
Multiply -4 times -1.
x=\frac{0±\sqrt{40}}{2\left(-1\right)}
Multiply 4 times 10.
x=\frac{0±2\sqrt{10}}{2\left(-1\right)}
Take the square root of 40.
x=\frac{0±2\sqrt{10}}{-2}
Multiply 2 times -1.
x=-\sqrt{10}
Now solve the equation x=\frac{0±2\sqrt{10}}{-2} when ± is plus.
x=\sqrt{10}
Now solve the equation x=\frac{0±2\sqrt{10}}{-2} when ± is minus.
x=-\sqrt{10} x=\sqrt{10}
The equation is now solved.
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Limits
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