Solve for x
x=7
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\sqrt{4x-3}=x-2
Subtract 2 from both sides of the equation.
\left(\sqrt{4x-3}\right)^{2}=\left(x-2\right)^{2}
Square both sides of the equation.
4x-3=\left(x-2\right)^{2}
Calculate \sqrt{4x-3} to the power of 2 and get 4x-3.
4x-3=x^{2}-4x+4
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(x-2\right)^{2}.
4x-3-x^{2}=-4x+4
Subtract x^{2} from both sides.
4x-3-x^{2}+4x=4
Add 4x to both sides.
8x-3-x^{2}=4
Combine 4x and 4x to get 8x.
8x-3-x^{2}-4=0
Subtract 4 from both sides.
8x-7-x^{2}=0
Subtract 4 from -3 to get -7.
-x^{2}+8x-7=0
Rearrange the polynomial to put it in standard form. Place the terms in order from highest to lowest power.
a+b=8 ab=-\left(-7\right)=7
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as -x^{2}+ax+bx-7. To find a and b, set up a system to be solved.
a=7 b=1
Since ab is positive, a and b have the same sign. Since a+b is positive, a and b are both positive. The only such pair is the system solution.
\left(-x^{2}+7x\right)+\left(x-7\right)
Rewrite -x^{2}+8x-7 as \left(-x^{2}+7x\right)+\left(x-7\right).
-x\left(x-7\right)+x-7
Factor out -x in -x^{2}+7x.
\left(x-7\right)\left(-x+1\right)
Factor out common term x-7 by using distributive property.
x=7 x=1
To find equation solutions, solve x-7=0 and -x+1=0.
\sqrt{4\times 7-3}+2=7
Substitute 7 for x in the equation \sqrt{4x-3}+2=x.
7=7
Simplify. The value x=7 satisfies the equation.
\sqrt{4\times 1-3}+2=1
Substitute 1 for x in the equation \sqrt{4x-3}+2=x.
3=1
Simplify. The value x=1 does not satisfy the equation.
x=7
Equation \sqrt{4x-3}=x-2 has a unique solution.
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y = 3x + 4
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Matrix
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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}