Solve for x
x = -\frac{5}{2} = -2\frac{1}{2} = -2.5
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x\left(2x+1\right)+\left(x-2\right)\times 4=-8
Variable x cannot be equal to any of the values 0,2 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-2,x,x^{2}-2x.
2x^{2}+x+\left(x-2\right)\times 4=-8
Use the distributive property to multiply x by 2x+1.
2x^{2}+x+4x-8=-8
Use the distributive property to multiply x-2 by 4.
2x^{2}+5x-8=-8
Combine x and 4x to get 5x.
2x^{2}+5x-8+8=0
Add 8 to both sides.
2x^{2}+5x=0
Add -8 and 8 to get 0.
x\left(2x+5\right)=0
Factor out x.
x=0 x=-\frac{5}{2}
To find equation solutions, solve x=0 and 2x+5=0.
x=-\frac{5}{2}
Variable x cannot be equal to 0.
x\left(2x+1\right)+\left(x-2\right)\times 4=-8
Variable x cannot be equal to any of the values 0,2 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-2,x,x^{2}-2x.
2x^{2}+x+\left(x-2\right)\times 4=-8
Use the distributive property to multiply x by 2x+1.
2x^{2}+x+4x-8=-8
Use the distributive property to multiply x-2 by 4.
2x^{2}+5x-8=-8
Combine x and 4x to get 5x.
2x^{2}+5x-8+8=0
Add 8 to both sides.
2x^{2}+5x=0
Add -8 and 8 to get 0.
x=\frac{-5±\sqrt{5^{2}}}{2\times 2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 2 for a, 5 for b, and 0 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-5±5}{2\times 2}
Take the square root of 5^{2}.
x=\frac{-5±5}{4}
Multiply 2 times 2.
x=\frac{0}{4}
Now solve the equation x=\frac{-5±5}{4} when ± is plus. Add -5 to 5.
x=0
Divide 0 by 4.
x=-\frac{10}{4}
Now solve the equation x=\frac{-5±5}{4} when ± is minus. Subtract 5 from -5.
x=-\frac{5}{2}
Reduce the fraction \frac{-10}{4} to lowest terms by extracting and canceling out 2.
x=0 x=-\frac{5}{2}
The equation is now solved.
x=-\frac{5}{2}
Variable x cannot be equal to 0.
x\left(2x+1\right)+\left(x-2\right)\times 4=-8
Variable x cannot be equal to any of the values 0,2 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-2,x,x^{2}-2x.
2x^{2}+x+\left(x-2\right)\times 4=-8
Use the distributive property to multiply x by 2x+1.
2x^{2}+x+4x-8=-8
Use the distributive property to multiply x-2 by 4.
2x^{2}+5x-8=-8
Combine x and 4x to get 5x.
2x^{2}+5x=-8+8
Add 8 to both sides.
2x^{2}+5x=0
Add -8 and 8 to get 0.
\frac{2x^{2}+5x}{2}=\frac{0}{2}
Divide both sides by 2.
x^{2}+\frac{5}{2}x=\frac{0}{2}
Dividing by 2 undoes the multiplication by 2.
x^{2}+\frac{5}{2}x=0
Divide 0 by 2.
x^{2}+\frac{5}{2}x+\left(\frac{5}{4}\right)^{2}=\left(\frac{5}{4}\right)^{2}
Divide \frac{5}{2}, the coefficient of the x term, by 2 to get \frac{5}{4}. Then add the square of \frac{5}{4} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+\frac{5}{2}x+\frac{25}{16}=\frac{25}{16}
Square \frac{5}{4} by squaring both the numerator and the denominator of the fraction.
\left(x+\frac{5}{4}\right)^{2}=\frac{25}{16}
Factor x^{2}+\frac{5}{2}x+\frac{25}{16}. 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+\frac{5}{4}\right)^{2}}=\sqrt{\frac{25}{16}}
Take the square root of both sides of the equation.
x+\frac{5}{4}=\frac{5}{4} x+\frac{5}{4}=-\frac{5}{4}
Simplify.
x=0 x=-\frac{5}{2}
Subtract \frac{5}{4} from both sides of the equation.
x=-\frac{5}{2}
Variable x cannot be equal to 0.
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