Solve for x
x = -\frac{5}{2} = -2\frac{1}{2} = -2.5
x=2
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\left(x+2\right)\times 5+\left(x+3\right)\times 4=2\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 \left(x+2\right)\left(x+3\right), the least common multiple of x+3,x+2.
5x+10+\left(x+3\right)\times 4=2\left(x+2\right)\left(x+3\right)
Use the distributive property to multiply x+2 by 5.
5x+10+4x+12=2\left(x+2\right)\left(x+3\right)
Use the distributive property to multiply x+3 by 4.
9x+10+12=2\left(x+2\right)\left(x+3\right)
Combine 5x and 4x to get 9x.
9x+22=2\left(x+2\right)\left(x+3\right)
Add 10 and 12 to get 22.
9x+22=\left(2x+4\right)\left(x+3\right)
Use the distributive property to multiply 2 by x+2.
9x+22=2x^{2}+10x+12
Use the distributive property to multiply 2x+4 by x+3 and combine like terms.
9x+22-2x^{2}=10x+12
Subtract 2x^{2} from both sides.
9x+22-2x^{2}-10x=12
Subtract 10x from both sides.
-x+22-2x^{2}=12
Combine 9x and -10x to get -x.
-x+22-2x^{2}-12=0
Subtract 12 from both sides.
-x+10-2x^{2}=0
Subtract 12 from 22 to get 10.
-2x^{2}-x+10=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(-1\right)±\sqrt{1-4\left(-2\right)\times 10}}{2\left(-2\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -2 for a, -1 for b, and 10 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-1\right)±\sqrt{1+8\times 10}}{2\left(-2\right)}
Multiply -4 times -2.
x=\frac{-\left(-1\right)±\sqrt{1+80}}{2\left(-2\right)}
Multiply 8 times 10.
x=\frac{-\left(-1\right)±\sqrt{81}}{2\left(-2\right)}
Add 1 to 80.
x=\frac{-\left(-1\right)±9}{2\left(-2\right)}
Take the square root of 81.
x=\frac{1±9}{2\left(-2\right)}
The opposite of -1 is 1.
x=\frac{1±9}{-4}
Multiply 2 times -2.
x=\frac{10}{-4}
Now solve the equation x=\frac{1±9}{-4} when ± is plus. Add 1 to 9.
x=-\frac{5}{2}
Reduce the fraction \frac{10}{-4} to lowest terms by extracting and canceling out 2.
x=-\frac{8}{-4}
Now solve the equation x=\frac{1±9}{-4} when ± is minus. Subtract 9 from 1.
x=2
Divide -8 by -4.
x=-\frac{5}{2} x=2
The equation is now solved.
\left(x+2\right)\times 5+\left(x+3\right)\times 4=2\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 \left(x+2\right)\left(x+3\right), the least common multiple of x+3,x+2.
5x+10+\left(x+3\right)\times 4=2\left(x+2\right)\left(x+3\right)
Use the distributive property to multiply x+2 by 5.
5x+10+4x+12=2\left(x+2\right)\left(x+3\right)
Use the distributive property to multiply x+3 by 4.
9x+10+12=2\left(x+2\right)\left(x+3\right)
Combine 5x and 4x to get 9x.
9x+22=2\left(x+2\right)\left(x+3\right)
Add 10 and 12 to get 22.
9x+22=\left(2x+4\right)\left(x+3\right)
Use the distributive property to multiply 2 by x+2.
9x+22=2x^{2}+10x+12
Use the distributive property to multiply 2x+4 by x+3 and combine like terms.
9x+22-2x^{2}=10x+12
Subtract 2x^{2} from both sides.
9x+22-2x^{2}-10x=12
Subtract 10x from both sides.
-x+22-2x^{2}=12
Combine 9x and -10x to get -x.
-x-2x^{2}=12-22
Subtract 22 from both sides.
-x-2x^{2}=-10
Subtract 22 from 12 to get -10.
-2x^{2}-x=-10
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{-2x^{2}-x}{-2}=-\frac{10}{-2}
Divide both sides by -2.
x^{2}+\left(-\frac{1}{-2}\right)x=-\frac{10}{-2}
Dividing by -2 undoes the multiplication by -2.
x^{2}+\frac{1}{2}x=-\frac{10}{-2}
Divide -1 by -2.
x^{2}+\frac{1}{2}x=5
Divide -10 by -2.
x^{2}+\frac{1}{2}x+\left(\frac{1}{4}\right)^{2}=5+\left(\frac{1}{4}\right)^{2}
Divide \frac{1}{2}, the coefficient of the x term, by 2 to get \frac{1}{4}. Then add the square of \frac{1}{4} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+\frac{1}{2}x+\frac{1}{16}=5+\frac{1}{16}
Square \frac{1}{4} by squaring both the numerator and the denominator of the fraction.
x^{2}+\frac{1}{2}x+\frac{1}{16}=\frac{81}{16}
Add 5 to \frac{1}{16}.
\left(x+\frac{1}{4}\right)^{2}=\frac{81}{16}
Factor x^{2}+\frac{1}{2}x+\frac{1}{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{1}{4}\right)^{2}}=\sqrt{\frac{81}{16}}
Take the square root of both sides of the equation.
x+\frac{1}{4}=\frac{9}{4} x+\frac{1}{4}=-\frac{9}{4}
Simplify.
x=2 x=-\frac{5}{2}
Subtract \frac{1}{4} from 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}