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10x-\frac{8x-3}{4}=2\left(x-3\right)\left(-x-3\right)
Variable x cannot be equal to -3 since division by zero is not defined. Multiply both sides of the equation by -x-3.
10x-\frac{8x-3}{4}=\left(2x-6\right)\left(-x-3\right)
Use the distributive property to multiply 2 by x-3.
10x-\frac{8x-3}{4}=-2x^{2}+18
Use the distributive property to multiply 2x-6 by -x-3 and combine like terms.
10x-\left(2x-\frac{3}{4}\right)=-2x^{2}+18
Divide each term of 8x-3 by 4 to get 2x-\frac{3}{4}.
10x-2x+\frac{3}{4}=-2x^{2}+18
To find the opposite of 2x-\frac{3}{4}, find the opposite of each term.
8x+\frac{3}{4}=-2x^{2}+18
Combine 10x and -2x to get 8x.
8x+\frac{3}{4}+2x^{2}=18
Add 2x^{2} to both sides.
8x+\frac{3}{4}+2x^{2}-18=0
Subtract 18 from both sides.
8x-\frac{69}{4}+2x^{2}=0
Subtract 18 from \frac{3}{4} to get -\frac{69}{4}.
2x^{2}+8x-\frac{69}{4}=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{-8±\sqrt{8^{2}-4\times 2\left(-\frac{69}{4}\right)}}{2\times 2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 2 for a, 8 for b, and -\frac{69}{4} for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-8±\sqrt{64-4\times 2\left(-\frac{69}{4}\right)}}{2\times 2}
Square 8.
x=\frac{-8±\sqrt{64-8\left(-\frac{69}{4}\right)}}{2\times 2}
Multiply -4 times 2.
x=\frac{-8±\sqrt{64+138}}{2\times 2}
Multiply -8 times -\frac{69}{4}.
x=\frac{-8±\sqrt{202}}{2\times 2}
Add 64 to 138.
x=\frac{-8±\sqrt{202}}{4}
Multiply 2 times 2.
x=\frac{\sqrt{202}-8}{4}
Now solve the equation x=\frac{-8±\sqrt{202}}{4} when ± is plus. Add -8 to \sqrt{202}.
x=\frac{\sqrt{202}}{4}-2
Divide -8+\sqrt{202} by 4.
x=\frac{-\sqrt{202}-8}{4}
Now solve the equation x=\frac{-8±\sqrt{202}}{4} when ± is minus. Subtract \sqrt{202} from -8.
x=-\frac{\sqrt{202}}{4}-2
Divide -8-\sqrt{202} by 4.
x=\frac{\sqrt{202}}{4}-2 x=-\frac{\sqrt{202}}{4}-2
The equation is now solved.
10x-\frac{8x-3}{4}=2\left(x-3\right)\left(-x-3\right)
Variable x cannot be equal to -3 since division by zero is not defined. Multiply both sides of the equation by -x-3.
10x-\frac{8x-3}{4}=\left(2x-6\right)\left(-x-3\right)
Use the distributive property to multiply 2 by x-3.
10x-\frac{8x-3}{4}=-2x^{2}+18
Use the distributive property to multiply 2x-6 by -x-3 and combine like terms.
10x-\left(2x-\frac{3}{4}\right)=-2x^{2}+18
Divide each term of 8x-3 by 4 to get 2x-\frac{3}{4}.
10x-2x+\frac{3}{4}=-2x^{2}+18
To find the opposite of 2x-\frac{3}{4}, find the opposite of each term.
8x+\frac{3}{4}=-2x^{2}+18
Combine 10x and -2x to get 8x.
8x+\frac{3}{4}+2x^{2}=18
Add 2x^{2} to both sides.
8x+2x^{2}=18-\frac{3}{4}
Subtract \frac{3}{4} from both sides.
8x+2x^{2}=\frac{69}{4}
Subtract \frac{3}{4} from 18 to get \frac{69}{4}.
2x^{2}+8x=\frac{69}{4}
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{2x^{2}+8x}{2}=\frac{\frac{69}{4}}{2}
Divide both sides by 2.
x^{2}+\frac{8}{2}x=\frac{\frac{69}{4}}{2}
Dividing by 2 undoes the multiplication by 2.
x^{2}+4x=\frac{\frac{69}{4}}{2}
Divide 8 by 2.
x^{2}+4x=\frac{69}{8}
Divide \frac{69}{4} by 2.
x^{2}+4x+2^{2}=\frac{69}{8}+2^{2}
Divide 4, the coefficient of the x term, by 2 to get 2. Then add the square of 2 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+4x+4=\frac{69}{8}+4
Square 2.
x^{2}+4x+4=\frac{101}{8}
Add \frac{69}{8} to 4.
\left(x+2\right)^{2}=\frac{101}{8}
Factor x^{2}+4x+4. 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+2\right)^{2}}=\sqrt{\frac{101}{8}}
Take the square root of both sides of the equation.
x+2=\frac{\sqrt{202}}{4} x+2=-\frac{\sqrt{202}}{4}
Simplify.
x=\frac{\sqrt{202}}{4}-2 x=-\frac{\sqrt{202}}{4}-2
Subtract 2 from both sides of the equation.