Solve for x
x = -\frac{40}{9} = -4\frac{4}{9} \approx -4.444444444
x=-1
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\left(2x+4\right)\left(4-3x\right)+\left(2x+6\right)\left(5x-1\right)=-5\left(x+2\right)\left(x+3\right)
Variable x cannot be equal to any of the values -3,-2 since division by zero is not defined. Multiply both sides of the equation by 2\left(x+2\right)\left(x+3\right), the least common multiple of x+3,x+2,2.
-4x-6x^{2}+16+\left(2x+6\right)\left(5x-1\right)=-5\left(x+2\right)\left(x+3\right)
Use the distributive property to multiply 2x+4 by 4-3x and combine like terms.
-4x-6x^{2}+16+10x^{2}+28x-6=-5\left(x+2\right)\left(x+3\right)
Use the distributive property to multiply 2x+6 by 5x-1 and combine like terms.
-4x+4x^{2}+16+28x-6=-5\left(x+2\right)\left(x+3\right)
Combine -6x^{2} and 10x^{2} to get 4x^{2}.
24x+4x^{2}+16-6=-5\left(x+2\right)\left(x+3\right)
Combine -4x and 28x to get 24x.
24x+4x^{2}+10=-5\left(x+2\right)\left(x+3\right)
Subtract 6 from 16 to get 10.
24x+4x^{2}+10=\left(-5x-10\right)\left(x+3\right)
Use the distributive property to multiply -5 by x+2.
24x+4x^{2}+10=-5x^{2}-25x-30
Use the distributive property to multiply -5x-10 by x+3 and combine like terms.
24x+4x^{2}+10+5x^{2}=-25x-30
Add 5x^{2} to both sides.
24x+9x^{2}+10=-25x-30
Combine 4x^{2} and 5x^{2} to get 9x^{2}.
24x+9x^{2}+10+25x=-30
Add 25x to both sides.
49x+9x^{2}+10=-30
Combine 24x and 25x to get 49x.
49x+9x^{2}+10+30=0
Add 30 to both sides.
49x+9x^{2}+40=0
Add 10 and 30 to get 40.
9x^{2}+49x+40=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{-49±\sqrt{49^{2}-4\times 9\times 40}}{2\times 9}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 9 for a, 49 for b, and 40 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-49±\sqrt{2401-4\times 9\times 40}}{2\times 9}
Square 49.
x=\frac{-49±\sqrt{2401-36\times 40}}{2\times 9}
Multiply -4 times 9.
x=\frac{-49±\sqrt{2401-1440}}{2\times 9}
Multiply -36 times 40.
x=\frac{-49±\sqrt{961}}{2\times 9}
Add 2401 to -1440.
x=\frac{-49±31}{2\times 9}
Take the square root of 961.
x=\frac{-49±31}{18}
Multiply 2 times 9.
x=-\frac{18}{18}
Now solve the equation x=\frac{-49±31}{18} when ± is plus. Add -49 to 31.
x=-1
Divide -18 by 18.
x=-\frac{80}{18}
Now solve the equation x=\frac{-49±31}{18} when ± is minus. Subtract 31 from -49.
x=-\frac{40}{9}
Reduce the fraction \frac{-80}{18} to lowest terms by extracting and canceling out 2.
x=-1 x=-\frac{40}{9}
The equation is now solved.
\left(2x+4\right)\left(4-3x\right)+\left(2x+6\right)\left(5x-1\right)=-5\left(x+2\right)\left(x+3\right)
Variable x cannot be equal to any of the values -3,-2 since division by zero is not defined. Multiply both sides of the equation by 2\left(x+2\right)\left(x+3\right), the least common multiple of x+3,x+2,2.
-4x-6x^{2}+16+\left(2x+6\right)\left(5x-1\right)=-5\left(x+2\right)\left(x+3\right)
Use the distributive property to multiply 2x+4 by 4-3x and combine like terms.
-4x-6x^{2}+16+10x^{2}+28x-6=-5\left(x+2\right)\left(x+3\right)
Use the distributive property to multiply 2x+6 by 5x-1 and combine like terms.
-4x+4x^{2}+16+28x-6=-5\left(x+2\right)\left(x+3\right)
Combine -6x^{2} and 10x^{2} to get 4x^{2}.
24x+4x^{2}+16-6=-5\left(x+2\right)\left(x+3\right)
Combine -4x and 28x to get 24x.
24x+4x^{2}+10=-5\left(x+2\right)\left(x+3\right)
Subtract 6 from 16 to get 10.
24x+4x^{2}+10=\left(-5x-10\right)\left(x+3\right)
Use the distributive property to multiply -5 by x+2.
24x+4x^{2}+10=-5x^{2}-25x-30
Use the distributive property to multiply -5x-10 by x+3 and combine like terms.
24x+4x^{2}+10+5x^{2}=-25x-30
Add 5x^{2} to both sides.
24x+9x^{2}+10=-25x-30
Combine 4x^{2} and 5x^{2} to get 9x^{2}.
24x+9x^{2}+10+25x=-30
Add 25x to both sides.
49x+9x^{2}+10=-30
Combine 24x and 25x to get 49x.
49x+9x^{2}=-30-10
Subtract 10 from both sides.
49x+9x^{2}=-40
Subtract 10 from -30 to get -40.
9x^{2}+49x=-40
Quadratic equations such as this one can be solved by completing the square. In order to complete the square, the equation must first be in the form x^{2}+bx=c.
\frac{9x^{2}+49x}{9}=-\frac{40}{9}
Divide both sides by 9.
x^{2}+\frac{49}{9}x=-\frac{40}{9}
Dividing by 9 undoes the multiplication by 9.
x^{2}+\frac{49}{9}x+\left(\frac{49}{18}\right)^{2}=-\frac{40}{9}+\left(\frac{49}{18}\right)^{2}
Divide \frac{49}{9}, the coefficient of the x term, by 2 to get \frac{49}{18}. Then add the square of \frac{49}{18} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+\frac{49}{9}x+\frac{2401}{324}=-\frac{40}{9}+\frac{2401}{324}
Square \frac{49}{18} by squaring both the numerator and the denominator of the fraction.
x^{2}+\frac{49}{9}x+\frac{2401}{324}=\frac{961}{324}
Add -\frac{40}{9} to \frac{2401}{324} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(x+\frac{49}{18}\right)^{2}=\frac{961}{324}
Factor x^{2}+\frac{49}{9}x+\frac{2401}{324}. 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{49}{18}\right)^{2}}=\sqrt{\frac{961}{324}}
Take the square root of both sides of the equation.
x+\frac{49}{18}=\frac{31}{18} x+\frac{49}{18}=-\frac{31}{18}
Simplify.
x=-1 x=-\frac{40}{9}
Subtract \frac{49}{18} from both sides of the equation.
Examples
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{ 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}