Solve for x
x=3
x=-\frac{1}{2}=-0.5
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Polynomial
5 problems similar to:
x ( 2 x - 5 ) - 6 ( x - 2 ) ^ { 2 } + 7 = 2 ( 5 - x ) ( x - 2 )
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2x^{2}-5x-6\left(x-2\right)^{2}+7=2\left(5-x\right)\left(x-2\right)
Use the distributive property to multiply x by 2x-5.
2x^{2}-5x-6\left(x^{2}-4x+4\right)+7=2\left(5-x\right)\left(x-2\right)
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(x-2\right)^{2}.
2x^{2}-5x-6x^{2}+24x-24+7=2\left(5-x\right)\left(x-2\right)
Use the distributive property to multiply -6 by x^{2}-4x+4.
-4x^{2}-5x+24x-24+7=2\left(5-x\right)\left(x-2\right)
Combine 2x^{2} and -6x^{2} to get -4x^{2}.
-4x^{2}+19x-24+7=2\left(5-x\right)\left(x-2\right)
Combine -5x and 24x to get 19x.
-4x^{2}+19x-17=2\left(5-x\right)\left(x-2\right)
Add -24 and 7 to get -17.
-4x^{2}+19x-17=\left(10-2x\right)\left(x-2\right)
Use the distributive property to multiply 2 by 5-x.
-4x^{2}+19x-17=14x-20-2x^{2}
Use the distributive property to multiply 10-2x by x-2 and combine like terms.
-4x^{2}+19x-17-14x=-20-2x^{2}
Subtract 14x from both sides.
-4x^{2}+5x-17=-20-2x^{2}
Combine 19x and -14x to get 5x.
-4x^{2}+5x-17-\left(-20\right)=-2x^{2}
Subtract -20 from both sides.
-4x^{2}+5x-17+20=-2x^{2}
The opposite of -20 is 20.
-4x^{2}+5x-17+20+2x^{2}=0
Add 2x^{2} to both sides.
-4x^{2}+5x+3+2x^{2}=0
Add -17 and 20 to get 3.
-2x^{2}+5x+3=0
Combine -4x^{2} and 2x^{2} to get -2x^{2}.
a+b=5 ab=-2\times 3=-6
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as -2x^{2}+ax+bx+3. To find a and b, set up a system to be solved.
-1,6 -2,3
Since ab is negative, a and b have the opposite signs. Since a+b is positive, the positive number has greater absolute value than the negative. List all such integer pairs that give product -6.
-1+6=5 -2+3=1
Calculate the sum for each pair.
a=6 b=-1
The solution is the pair that gives sum 5.
\left(-2x^{2}+6x\right)+\left(-x+3\right)
Rewrite -2x^{2}+5x+3 as \left(-2x^{2}+6x\right)+\left(-x+3\right).
2x\left(-x+3\right)-x+3
Factor out 2x in -2x^{2}+6x.
\left(-x+3\right)\left(2x+1\right)
Factor out common term -x+3 by using distributive property.
x=3 x=-\frac{1}{2}
To find equation solutions, solve -x+3=0 and 2x+1=0.
2x^{2}-5x-6\left(x-2\right)^{2}+7=2\left(5-x\right)\left(x-2\right)
Use the distributive property to multiply x by 2x-5.
2x^{2}-5x-6\left(x^{2}-4x+4\right)+7=2\left(5-x\right)\left(x-2\right)
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(x-2\right)^{2}.
2x^{2}-5x-6x^{2}+24x-24+7=2\left(5-x\right)\left(x-2\right)
Use the distributive property to multiply -6 by x^{2}-4x+4.
-4x^{2}-5x+24x-24+7=2\left(5-x\right)\left(x-2\right)
Combine 2x^{2} and -6x^{2} to get -4x^{2}.
-4x^{2}+19x-24+7=2\left(5-x\right)\left(x-2\right)
Combine -5x and 24x to get 19x.
-4x^{2}+19x-17=2\left(5-x\right)\left(x-2\right)
Add -24 and 7 to get -17.
-4x^{2}+19x-17=\left(10-2x\right)\left(x-2\right)
Use the distributive property to multiply 2 by 5-x.
-4x^{2}+19x-17=14x-20-2x^{2}
Use the distributive property to multiply 10-2x by x-2 and combine like terms.
-4x^{2}+19x-17-14x=-20-2x^{2}
Subtract 14x from both sides.
-4x^{2}+5x-17=-20-2x^{2}
Combine 19x and -14x to get 5x.
-4x^{2}+5x-17-\left(-20\right)=-2x^{2}
Subtract -20 from both sides.
-4x^{2}+5x-17+20=-2x^{2}
The opposite of -20 is 20.
-4x^{2}+5x-17+20+2x^{2}=0
Add 2x^{2} to both sides.
-4x^{2}+5x+3+2x^{2}=0
Add -17 and 20 to get 3.
-2x^{2}+5x+3=0
Combine -4x^{2} and 2x^{2} to get -2x^{2}.
x=\frac{-5±\sqrt{5^{2}-4\left(-2\right)\times 3}}{2\left(-2\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -2 for a, 5 for b, and 3 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-5±\sqrt{25-4\left(-2\right)\times 3}}{2\left(-2\right)}
Square 5.
x=\frac{-5±\sqrt{25+8\times 3}}{2\left(-2\right)}
Multiply -4 times -2.
x=\frac{-5±\sqrt{25+24}}{2\left(-2\right)}
Multiply 8 times 3.
x=\frac{-5±\sqrt{49}}{2\left(-2\right)}
Add 25 to 24.
x=\frac{-5±7}{2\left(-2\right)}
Take the square root of 49.
x=\frac{-5±7}{-4}
Multiply 2 times -2.
x=\frac{2}{-4}
Now solve the equation x=\frac{-5±7}{-4} when ± is plus. Add -5 to 7.
x=-\frac{1}{2}
Reduce the fraction \frac{2}{-4} to lowest terms by extracting and canceling out 2.
x=-\frac{12}{-4}
Now solve the equation x=\frac{-5±7}{-4} when ± is minus. Subtract 7 from -5.
x=3
Divide -12 by -4.
x=-\frac{1}{2} x=3
The equation is now solved.
2x^{2}-5x-6\left(x-2\right)^{2}+7=2\left(5-x\right)\left(x-2\right)
Use the distributive property to multiply x by 2x-5.
2x^{2}-5x-6\left(x^{2}-4x+4\right)+7=2\left(5-x\right)\left(x-2\right)
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(x-2\right)^{2}.
2x^{2}-5x-6x^{2}+24x-24+7=2\left(5-x\right)\left(x-2\right)
Use the distributive property to multiply -6 by x^{2}-4x+4.
-4x^{2}-5x+24x-24+7=2\left(5-x\right)\left(x-2\right)
Combine 2x^{2} and -6x^{2} to get -4x^{2}.
-4x^{2}+19x-24+7=2\left(5-x\right)\left(x-2\right)
Combine -5x and 24x to get 19x.
-4x^{2}+19x-17=2\left(5-x\right)\left(x-2\right)
Add -24 and 7 to get -17.
-4x^{2}+19x-17=\left(10-2x\right)\left(x-2\right)
Use the distributive property to multiply 2 by 5-x.
-4x^{2}+19x-17=14x-20-2x^{2}
Use the distributive property to multiply 10-2x by x-2 and combine like terms.
-4x^{2}+19x-17-14x=-20-2x^{2}
Subtract 14x from both sides.
-4x^{2}+5x-17=-20-2x^{2}
Combine 19x and -14x to get 5x.
-4x^{2}+5x-17+2x^{2}=-20
Add 2x^{2} to both sides.
-2x^{2}+5x-17=-20
Combine -4x^{2} and 2x^{2} to get -2x^{2}.
-2x^{2}+5x=-20+17
Add 17 to both sides.
-2x^{2}+5x=-3
Add -20 and 17 to get -3.
\frac{-2x^{2}+5x}{-2}=-\frac{3}{-2}
Divide both sides by -2.
x^{2}+\frac{5}{-2}x=-\frac{3}{-2}
Dividing by -2 undoes the multiplication by -2.
x^{2}-\frac{5}{2}x=-\frac{3}{-2}
Divide 5 by -2.
x^{2}-\frac{5}{2}x=\frac{3}{2}
Divide -3 by -2.
x^{2}-\frac{5}{2}x+\left(-\frac{5}{4}\right)^{2}=\frac{3}{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{3}{2}+\frac{25}{16}
Square -\frac{5}{4} by squaring both the numerator and the denominator of the fraction.
x^{2}-\frac{5}{2}x+\frac{25}{16}=\frac{49}{16}
Add \frac{3}{2} to \frac{25}{16} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(x-\frac{5}{4}\right)^{2}=\frac{49}{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{49}{16}}
Take the square root of both sides of the equation.
x-\frac{5}{4}=\frac{7}{4} x-\frac{5}{4}=-\frac{7}{4}
Simplify.
x=3 x=-\frac{1}{2}
Add \frac{5}{4} to both sides of the equation.
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}