Solve for x
x=-6
x=0
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\left(5x+5\right)\left(x+3\right)+\left(5x+25\right)\times 2=13\left(x+1\right)\left(x+5\right)
Variable x cannot be equal to any of the values -5,-1 since division by zero is not defined. Multiply both sides of the equation by 5\left(x+1\right)\left(x+5\right), the least common multiple of x+5,x+1,5.
5x^{2}+20x+15+\left(5x+25\right)\times 2=13\left(x+1\right)\left(x+5\right)
Use the distributive property to multiply 5x+5 by x+3 and combine like terms.
5x^{2}+20x+15+10x+50=13\left(x+1\right)\left(x+5\right)
Use the distributive property to multiply 5x+25 by 2.
5x^{2}+30x+15+50=13\left(x+1\right)\left(x+5\right)
Combine 20x and 10x to get 30x.
5x^{2}+30x+65=13\left(x+1\right)\left(x+5\right)
Add 15 and 50 to get 65.
5x^{2}+30x+65=\left(13x+13\right)\left(x+5\right)
Use the distributive property to multiply 13 by x+1.
5x^{2}+30x+65=13x^{2}+78x+65
Use the distributive property to multiply 13x+13 by x+5 and combine like terms.
5x^{2}+30x+65-13x^{2}=78x+65
Subtract 13x^{2} from both sides.
-8x^{2}+30x+65=78x+65
Combine 5x^{2} and -13x^{2} to get -8x^{2}.
-8x^{2}+30x+65-78x=65
Subtract 78x from both sides.
-8x^{2}-48x+65=65
Combine 30x and -78x to get -48x.
-8x^{2}-48x+65-65=0
Subtract 65 from both sides.
-8x^{2}-48x=0
Subtract 65 from 65 to get 0.
x=\frac{-\left(-48\right)±\sqrt{\left(-48\right)^{2}}}{2\left(-8\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -8 for a, -48 for b, and 0 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-48\right)±48}{2\left(-8\right)}
Take the square root of \left(-48\right)^{2}.
x=\frac{48±48}{2\left(-8\right)}
The opposite of -48 is 48.
x=\frac{48±48}{-16}
Multiply 2 times -8.
x=\frac{96}{-16}
Now solve the equation x=\frac{48±48}{-16} when ± is plus. Add 48 to 48.
x=-6
Divide 96 by -16.
x=\frac{0}{-16}
Now solve the equation x=\frac{48±48}{-16} when ± is minus. Subtract 48 from 48.
x=0
Divide 0 by -16.
x=-6 x=0
The equation is now solved.
\left(5x+5\right)\left(x+3\right)+\left(5x+25\right)\times 2=13\left(x+1\right)\left(x+5\right)
Variable x cannot be equal to any of the values -5,-1 since division by zero is not defined. Multiply both sides of the equation by 5\left(x+1\right)\left(x+5\right), the least common multiple of x+5,x+1,5.
5x^{2}+20x+15+\left(5x+25\right)\times 2=13\left(x+1\right)\left(x+5\right)
Use the distributive property to multiply 5x+5 by x+3 and combine like terms.
5x^{2}+20x+15+10x+50=13\left(x+1\right)\left(x+5\right)
Use the distributive property to multiply 5x+25 by 2.
5x^{2}+30x+15+50=13\left(x+1\right)\left(x+5\right)
Combine 20x and 10x to get 30x.
5x^{2}+30x+65=13\left(x+1\right)\left(x+5\right)
Add 15 and 50 to get 65.
5x^{2}+30x+65=\left(13x+13\right)\left(x+5\right)
Use the distributive property to multiply 13 by x+1.
5x^{2}+30x+65=13x^{2}+78x+65
Use the distributive property to multiply 13x+13 by x+5 and combine like terms.
5x^{2}+30x+65-13x^{2}=78x+65
Subtract 13x^{2} from both sides.
-8x^{2}+30x+65=78x+65
Combine 5x^{2} and -13x^{2} to get -8x^{2}.
-8x^{2}+30x+65-78x=65
Subtract 78x from both sides.
-8x^{2}-48x+65=65
Combine 30x and -78x to get -48x.
-8x^{2}-48x=65-65
Subtract 65 from both sides.
-8x^{2}-48x=0
Subtract 65 from 65 to get 0.
\frac{-8x^{2}-48x}{-8}=\frac{0}{-8}
Divide both sides by -8.
x^{2}+\left(-\frac{48}{-8}\right)x=\frac{0}{-8}
Dividing by -8 undoes the multiplication by -8.
x^{2}+6x=\frac{0}{-8}
Divide -48 by -8.
x^{2}+6x=0
Divide 0 by -8.
x^{2}+6x+3^{2}=3^{2}
Divide 6, the coefficient of the x term, by 2 to get 3. Then add the square of 3 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+6x+9=9
Square 3.
\left(x+3\right)^{2}=9
Factor x^{2}+6x+9. 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+3\right)^{2}}=\sqrt{9}
Take the square root of both sides of the equation.
x+3=3 x+3=-3
Simplify.
x=0 x=-6
Subtract 3 from both sides of the equation.
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Matrix
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Simultaneous equation
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Differentiation
\frac { d } { d x } \frac { ( 3 x ^ { 2 } - 2 ) } { ( x - 5 ) }
Integration
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Limits
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