Solve for x
x=2
x=-2
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10\times 6-2x\times 7x=xx
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 10x, the least common multiple of x,5,10.
10\times 6-2x\times 7x=x^{2}
Multiply x and x to get x^{2}.
60-2x\times 7x=x^{2}
Multiply 10 and 6 to get 60.
60-2x^{2}\times 7=x^{2}
Multiply x and x to get x^{2}.
60-14x^{2}=x^{2}
Multiply 2 and 7 to get 14.
60-14x^{2}-x^{2}=0
Subtract x^{2} from both sides.
-14x^{2}-x^{2}=-60
Subtract 60 from both sides. Anything subtracted from zero gives its negation.
-15x^{2}=-60
Combine -14x^{2} and -x^{2} to get -15x^{2}.
x^{2}=\frac{-60}{-15}
Divide both sides by -15.
x^{2}=4
Divide -60 by -15 to get 4.
x=2 x=-2
Take the square root of both sides of the equation.
10\times 6-2x\times 7x=xx
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 10x, the least common multiple of x,5,10.
10\times 6-2x\times 7x=x^{2}
Multiply x and x to get x^{2}.
60-2x\times 7x=x^{2}
Multiply 10 and 6 to get 60.
60-2x^{2}\times 7=x^{2}
Multiply x and x to get x^{2}.
60-14x^{2}=x^{2}
Multiply 2 and 7 to get 14.
60-14x^{2}-x^{2}=0
Subtract x^{2} from both sides.
60-15x^{2}=0
Combine -14x^{2} and -x^{2} to get -15x^{2}.
-15x^{2}+60=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(-15\right)\times 60}}{2\left(-15\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -15 for a, 0 for b, and 60 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\left(-15\right)\times 60}}{2\left(-15\right)}
Square 0.
x=\frac{0±\sqrt{60\times 60}}{2\left(-15\right)}
Multiply -4 times -15.
x=\frac{0±\sqrt{3600}}{2\left(-15\right)}
Multiply 60 times 60.
x=\frac{0±60}{2\left(-15\right)}
Take the square root of 3600.
x=\frac{0±60}{-30}
Multiply 2 times -15.
x=-2
Now solve the equation x=\frac{0±60}{-30} when ± is plus. Divide 60 by -30.
x=2
Now solve the equation x=\frac{0±60}{-30} when ± is minus. Divide -60 by -30.
x=-2 x=2
The equation is now solved.
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