Solve for x
x = \frac{8}{5} = 1\frac{3}{5} = 1.6
Graph
Share
Copied to clipboard
2+\sqrt{4-x^{2}}=2x
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by x.
2+\sqrt{4-x^{2}}-2x=0
Subtract 2x from both sides.
\sqrt{4-x^{2}}=-\left(2-2x\right)
Subtract 2-2x from both sides of the equation.
\sqrt{4-x^{2}}=-2+2x
To find the opposite of 2-2x, find the opposite of each term.
\left(\sqrt{4-x^{2}}\right)^{2}=\left(-2+2x\right)^{2}
Square both sides of the equation.
4-x^{2}=\left(-2+2x\right)^{2}
Calculate \sqrt{4-x^{2}} to the power of 2 and get 4-x^{2}.
4-x^{2}=4-8x+4x^{2}
Use binomial theorem \left(a+b\right)^{2}=a^{2}+2ab+b^{2} to expand \left(-2+2x\right)^{2}.
4-x^{2}-4=-8x+4x^{2}
Subtract 4 from both sides.
-x^{2}=-8x+4x^{2}
Subtract 4 from 4 to get 0.
-x^{2}+8x=4x^{2}
Add 8x to both sides.
-x^{2}+8x-4x^{2}=0
Subtract 4x^{2} from both sides.
-5x^{2}+8x=0
Combine -x^{2} and -4x^{2} to get -5x^{2}.
x\left(-5x+8\right)=0
Factor out x.
x=0 x=\frac{8}{5}
To find equation solutions, solve x=0 and -5x+8=0.
\frac{2+\sqrt{4-0^{2}}}{0}=2
Substitute 0 for x in the equation \frac{2+\sqrt{4-x^{2}}}{x}=2. The expression is undefined.
\frac{2+\sqrt{4-\left(\frac{8}{5}\right)^{2}}}{\frac{8}{5}}=2
Substitute \frac{8}{5} for x in the equation \frac{2+\sqrt{4-x^{2}}}{x}=2.
2=2
Simplify. The value x=\frac{8}{5} satisfies the equation.
x=\frac{8}{5}
Equation \sqrt{4-x^{2}}=2x-2 has a unique solution.
Examples
Quadratic equation
{ x } ^ { 2 } - 4 x - 5 = 0
Trigonometry
4 \sin \theta \cos \theta = 2 \sin \theta
Linear equation
y = 3x + 4
Arithmetic
699 * 533
Matrix
\left[ \begin{array} { l l } { 2 } & { 3 } \\ { 5 } & { 4 } \end{array} \right] \left[ \begin{array} { l l l } { 2 } & { 0 } & { 3 } \\ { -1 } & { 1 } & { 5 } \end{array} \right]
Simultaneous equation
\left. \begin{cases} { 8x+2y = 46 } \\ { 7x+3y = 47 } \end{cases} \right.
Differentiation
\frac { d } { d x } \frac { ( 3 x ^ { 2 } - 2 ) } { ( x - 5 ) }
Integration
\int _ { 0 } ^ { 1 } x e ^ { - x ^ { 2 } } d x
Limits
\lim _{x \rightarrow-3} \frac{x^{2}-9}{x^{2}+2 x-3}