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-2\times 4+2x\times 0.5x=4x-1
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 4x, the least common multiple of 2x,2,4x.
-8+2x\times 0.5x=4x-1
Multiply -2 and 4 to get -8.
-8+2x^{2}\times 0.5=4x-1
Multiply x and x to get x^{2}.
-8+x^{2}=4x-1
Multiply 2 and 0.5 to get 1.
-8+x^{2}-4x=-1
Subtract 4x from both sides.
-8+x^{2}-4x+1=0
Add 1 to both sides.
-7+x^{2}-4x=0
Add -8 and 1 to get -7.
x^{2}-4x-7=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{-\left(-4\right)±\sqrt{\left(-4\right)^{2}-4\left(-7\right)}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, -4 for b, and -7 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-4\right)±\sqrt{16-4\left(-7\right)}}{2}
Square -4.
x=\frac{-\left(-4\right)±\sqrt{16+28}}{2}
Multiply -4 times -7.
x=\frac{-\left(-4\right)±\sqrt{44}}{2}
Add 16 to 28.
x=\frac{-\left(-4\right)±2\sqrt{11}}{2}
Take the square root of 44.
x=\frac{4±2\sqrt{11}}{2}
The opposite of -4 is 4.
x=\frac{2\sqrt{11}+4}{2}
Now solve the equation x=\frac{4±2\sqrt{11}}{2} when ± is plus. Add 4 to 2\sqrt{11}.
x=\sqrt{11}+2
Divide 4+2\sqrt{11} by 2.
x=\frac{4-2\sqrt{11}}{2}
Now solve the equation x=\frac{4±2\sqrt{11}}{2} when ± is minus. Subtract 2\sqrt{11} from 4.
x=2-\sqrt{11}
Divide 4-2\sqrt{11} by 2.
x=\sqrt{11}+2 x=2-\sqrt{11}
The equation is now solved.
-2\times 4+2x\times 0.5x=4x-1
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 4x, the least common multiple of 2x,2,4x.
-8+2x\times 0.5x=4x-1
Multiply -2 and 4 to get -8.
-8+2x^{2}\times 0.5=4x-1
Multiply x and x to get x^{2}.
-8+x^{2}=4x-1
Multiply 2 and 0.5 to get 1.
-8+x^{2}-4x=-1
Subtract 4x from both sides.
x^{2}-4x=-1+8
Add 8 to both sides.
x^{2}-4x=7
Add -1 and 8 to get 7.
x^{2}-4x+\left(-2\right)^{2}=7+\left(-2\right)^{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=7+4
Square -2.
x^{2}-4x+4=11
Add 7 to 4.
\left(x-2\right)^{2}=11
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{11}
Take the square root of both sides of the equation.
x-2=\sqrt{11} x-2=-\sqrt{11}
Simplify.
x=\sqrt{11}+2 x=2-\sqrt{11}
Add 2 to both sides of the equation.