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x\times 34-xx=288
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by x.
x\times 34-x^{2}=288
Multiply x and x to get x^{2}.
x\times 34-x^{2}-288=0
Subtract 288 from both sides.
-x^{2}+34x-288=0
All equations of the form ax^{2}+bx+c=0 can be solved using the quadratic formula: \frac{-b±\sqrt{b^{2}-4ac}}{2a}. The quadratic formula gives two solutions, one when ± is addition and one when it is subtraction.
x=\frac{-34±\sqrt{34^{2}-4\left(-1\right)\left(-288\right)}}{2\left(-1\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -1 for a, 34 for b, and -288 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-34±\sqrt{1156-4\left(-1\right)\left(-288\right)}}{2\left(-1\right)}
Square 34.
x=\frac{-34±\sqrt{1156+4\left(-288\right)}}{2\left(-1\right)}
Multiply -4 times -1.
x=\frac{-34±\sqrt{1156-1152}}{2\left(-1\right)}
Multiply 4 times -288.
x=\frac{-34±\sqrt{4}}{2\left(-1\right)}
Add 1156 to -1152.
x=\frac{-34±2}{2\left(-1\right)}
Take the square root of 4.
x=\frac{-34±2}{-2}
Multiply 2 times -1.
x=-\frac{32}{-2}
Now solve the equation x=\frac{-34±2}{-2} when ± is plus. Add -34 to 2.
x=16
Divide -32 by -2.
x=-\frac{36}{-2}
Now solve the equation x=\frac{-34±2}{-2} when ± is minus. Subtract 2 from -34.
x=18
Divide -36 by -2.
x=16 x=18
The equation is now solved.
x\times 34-xx=288
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by x.
x\times 34-x^{2}=288
Multiply x and x to get x^{2}.
-x^{2}+34x=288
Quadratic equations such as this one can be solved by completing the square. In order to complete the square, the equation must first be in the form x^{2}+bx=c.
\frac{-x^{2}+34x}{-1}=\frac{288}{-1}
Divide both sides by -1.
x^{2}+\frac{34}{-1}x=\frac{288}{-1}
Dividing by -1 undoes the multiplication by -1.
x^{2}-34x=\frac{288}{-1}
Divide 34 by -1.
x^{2}-34x=-288
Divide 288 by -1.
x^{2}-34x+\left(-17\right)^{2}=-288+\left(-17\right)^{2}
Divide -34, the coefficient of the x term, by 2 to get -17. Then add the square of -17 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-34x+289=-288+289
Square -17.
x^{2}-34x+289=1
Add -288 to 289.
\left(x-17\right)^{2}=1
Factor x^{2}-34x+289. In general, when x^{2}+bx+c is a perfect square, it can always be factored as \left(x+\frac{b}{2}\right)^{2}.
\sqrt{\left(x-17\right)^{2}}=\sqrt{1}
Take the square root of both sides of the equation.
x-17=1 x-17=-1
Simplify.
x=18 x=16
Add 17 to both sides of the equation.