Solve for x
x=-7
x=9
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\left(2x-3\right)\left(x+5\right)=\left(x+6\right)\left(3x-13\right)
Variable x cannot be equal to any of the values -6,\frac{3}{2} since division by zero is not defined. Multiply both sides of the equation by \left(2x-3\right)\left(x+6\right), the least common multiple of x+6,2x-3.
2x^{2}+7x-15=\left(x+6\right)\left(3x-13\right)
Use the distributive property to multiply 2x-3 by x+5 and combine like terms.
2x^{2}+7x-15=3x^{2}+5x-78
Use the distributive property to multiply x+6 by 3x-13 and combine like terms.
2x^{2}+7x-15-3x^{2}=5x-78
Subtract 3x^{2} from both sides.
-x^{2}+7x-15=5x-78
Combine 2x^{2} and -3x^{2} to get -x^{2}.
-x^{2}+7x-15-5x=-78
Subtract 5x from both sides.
-x^{2}+2x-15=-78
Combine 7x and -5x to get 2x.
-x^{2}+2x-15+78=0
Add 78 to both sides.
-x^{2}+2x+63=0
Add -15 and 78 to get 63.
x=\frac{-2±\sqrt{2^{2}-4\left(-1\right)\times 63}}{2\left(-1\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -1 for a, 2 for b, and 63 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-2±\sqrt{4-4\left(-1\right)\times 63}}{2\left(-1\right)}
Square 2.
x=\frac{-2±\sqrt{4+4\times 63}}{2\left(-1\right)}
Multiply -4 times -1.
x=\frac{-2±\sqrt{4+252}}{2\left(-1\right)}
Multiply 4 times 63.
x=\frac{-2±\sqrt{256}}{2\left(-1\right)}
Add 4 to 252.
x=\frac{-2±16}{2\left(-1\right)}
Take the square root of 256.
x=\frac{-2±16}{-2}
Multiply 2 times -1.
x=\frac{14}{-2}
Now solve the equation x=\frac{-2±16}{-2} when ± is plus. Add -2 to 16.
x=-7
Divide 14 by -2.
x=-\frac{18}{-2}
Now solve the equation x=\frac{-2±16}{-2} when ± is minus. Subtract 16 from -2.
x=9
Divide -18 by -2.
x=-7 x=9
The equation is now solved.
\left(2x-3\right)\left(x+5\right)=\left(x+6\right)\left(3x-13\right)
Variable x cannot be equal to any of the values -6,\frac{3}{2} since division by zero is not defined. Multiply both sides of the equation by \left(2x-3\right)\left(x+6\right), the least common multiple of x+6,2x-3.
2x^{2}+7x-15=\left(x+6\right)\left(3x-13\right)
Use the distributive property to multiply 2x-3 by x+5 and combine like terms.
2x^{2}+7x-15=3x^{2}+5x-78
Use the distributive property to multiply x+6 by 3x-13 and combine like terms.
2x^{2}+7x-15-3x^{2}=5x-78
Subtract 3x^{2} from both sides.
-x^{2}+7x-15=5x-78
Combine 2x^{2} and -3x^{2} to get -x^{2}.
-x^{2}+7x-15-5x=-78
Subtract 5x from both sides.
-x^{2}+2x-15=-78
Combine 7x and -5x to get 2x.
-x^{2}+2x=-78+15
Add 15 to both sides.
-x^{2}+2x=-63
Add -78 and 15 to get -63.
\frac{-x^{2}+2x}{-1}=-\frac{63}{-1}
Divide both sides by -1.
x^{2}+\frac{2}{-1}x=-\frac{63}{-1}
Dividing by -1 undoes the multiplication by -1.
x^{2}-2x=-\frac{63}{-1}
Divide 2 by -1.
x^{2}-2x=63
Divide -63 by -1.
x^{2}-2x+1=63+1
Divide -2, the coefficient of the x term, by 2 to get -1. Then add the square of -1 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-2x+1=64
Add 63 to 1.
\left(x-1\right)^{2}=64
Factor x^{2}-2x+1. 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-1\right)^{2}}=\sqrt{64}
Take the square root of both sides of the equation.
x-1=8 x-1=-8
Simplify.
x=9 x=-7
Add 1 to both sides of the equation.
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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
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Limits
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