Solve for x
x = -\frac{23}{10} = -2\frac{3}{10} = -2.3
x=1
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\left(2x+5\right)\times 3+14+\left(2x-3\right)\left(2x+5\right)\times 5=0
Variable x cannot be equal to any of the values -\frac{5}{2},\frac{3}{2} since division by zero is not defined. Multiply both sides of the equation by \left(2x-3\right)\left(2x+5\right), the least common multiple of 2x-3,4x^{2}+4x-15.
6x+15+14+\left(2x-3\right)\left(2x+5\right)\times 5=0
Use the distributive property to multiply 2x+5 by 3.
6x+29+\left(2x-3\right)\left(2x+5\right)\times 5=0
Add 15 and 14 to get 29.
6x+29+\left(4x^{2}+4x-15\right)\times 5=0
Use the distributive property to multiply 2x-3 by 2x+5 and combine like terms.
6x+29+20x^{2}+20x-75=0
Use the distributive property to multiply 4x^{2}+4x-15 by 5.
26x+29+20x^{2}-75=0
Combine 6x and 20x to get 26x.
26x-46+20x^{2}=0
Subtract 75 from 29 to get -46.
13x-23+10x^{2}=0
Divide both sides by 2.
10x^{2}+13x-23=0
Rearrange the polynomial to put it in standard form. Place the terms in order from highest to lowest power.
a+b=13 ab=10\left(-23\right)=-230
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as 10x^{2}+ax+bx-23. To find a and b, set up a system to be solved.
-1,230 -2,115 -5,46 -10,23
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 -230.
-1+230=229 -2+115=113 -5+46=41 -10+23=13
Calculate the sum for each pair.
a=-10 b=23
The solution is the pair that gives sum 13.
\left(10x^{2}-10x\right)+\left(23x-23\right)
Rewrite 10x^{2}+13x-23 as \left(10x^{2}-10x\right)+\left(23x-23\right).
10x\left(x-1\right)+23\left(x-1\right)
Factor out 10x in the first and 23 in the second group.
\left(x-1\right)\left(10x+23\right)
Factor out common term x-1 by using distributive property.
x=1 x=-\frac{23}{10}
To find equation solutions, solve x-1=0 and 10x+23=0.
\left(2x+5\right)\times 3+14+\left(2x-3\right)\left(2x+5\right)\times 5=0
Variable x cannot be equal to any of the values -\frac{5}{2},\frac{3}{2} since division by zero is not defined. Multiply both sides of the equation by \left(2x-3\right)\left(2x+5\right), the least common multiple of 2x-3,4x^{2}+4x-15.
6x+15+14+\left(2x-3\right)\left(2x+5\right)\times 5=0
Use the distributive property to multiply 2x+5 by 3.
6x+29+\left(2x-3\right)\left(2x+5\right)\times 5=0
Add 15 and 14 to get 29.
6x+29+\left(4x^{2}+4x-15\right)\times 5=0
Use the distributive property to multiply 2x-3 by 2x+5 and combine like terms.
6x+29+20x^{2}+20x-75=0
Use the distributive property to multiply 4x^{2}+4x-15 by 5.
26x+29+20x^{2}-75=0
Combine 6x and 20x to get 26x.
26x-46+20x^{2}=0
Subtract 75 from 29 to get -46.
20x^{2}+26x-46=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{-26±\sqrt{26^{2}-4\times 20\left(-46\right)}}{2\times 20}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 20 for a, 26 for b, and -46 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-26±\sqrt{676-4\times 20\left(-46\right)}}{2\times 20}
Square 26.
x=\frac{-26±\sqrt{676-80\left(-46\right)}}{2\times 20}
Multiply -4 times 20.
x=\frac{-26±\sqrt{676+3680}}{2\times 20}
Multiply -80 times -46.
x=\frac{-26±\sqrt{4356}}{2\times 20}
Add 676 to 3680.
x=\frac{-26±66}{2\times 20}
Take the square root of 4356.
x=\frac{-26±66}{40}
Multiply 2 times 20.
x=\frac{40}{40}
Now solve the equation x=\frac{-26±66}{40} when ± is plus. Add -26 to 66.
x=1
Divide 40 by 40.
x=-\frac{92}{40}
Now solve the equation x=\frac{-26±66}{40} when ± is minus. Subtract 66 from -26.
x=-\frac{23}{10}
Reduce the fraction \frac{-92}{40} to lowest terms by extracting and canceling out 4.
x=1 x=-\frac{23}{10}
The equation is now solved.
\left(2x+5\right)\times 3+14+\left(2x-3\right)\left(2x+5\right)\times 5=0
Variable x cannot be equal to any of the values -\frac{5}{2},\frac{3}{2} since division by zero is not defined. Multiply both sides of the equation by \left(2x-3\right)\left(2x+5\right), the least common multiple of 2x-3,4x^{2}+4x-15.
6x+15+14+\left(2x-3\right)\left(2x+5\right)\times 5=0
Use the distributive property to multiply 2x+5 by 3.
6x+29+\left(2x-3\right)\left(2x+5\right)\times 5=0
Add 15 and 14 to get 29.
6x+29+\left(4x^{2}+4x-15\right)\times 5=0
Use the distributive property to multiply 2x-3 by 2x+5 and combine like terms.
6x+29+20x^{2}+20x-75=0
Use the distributive property to multiply 4x^{2}+4x-15 by 5.
26x+29+20x^{2}-75=0
Combine 6x and 20x to get 26x.
26x-46+20x^{2}=0
Subtract 75 from 29 to get -46.
26x+20x^{2}=46
Add 46 to both sides. Anything plus zero gives itself.
20x^{2}+26x=46
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{20x^{2}+26x}{20}=\frac{46}{20}
Divide both sides by 20.
x^{2}+\frac{26}{20}x=\frac{46}{20}
Dividing by 20 undoes the multiplication by 20.
x^{2}+\frac{13}{10}x=\frac{46}{20}
Reduce the fraction \frac{26}{20} to lowest terms by extracting and canceling out 2.
x^{2}+\frac{13}{10}x=\frac{23}{10}
Reduce the fraction \frac{46}{20} to lowest terms by extracting and canceling out 2.
x^{2}+\frac{13}{10}x+\left(\frac{13}{20}\right)^{2}=\frac{23}{10}+\left(\frac{13}{20}\right)^{2}
Divide \frac{13}{10}, the coefficient of the x term, by 2 to get \frac{13}{20}. Then add the square of \frac{13}{20} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+\frac{13}{10}x+\frac{169}{400}=\frac{23}{10}+\frac{169}{400}
Square \frac{13}{20} by squaring both the numerator and the denominator of the fraction.
x^{2}+\frac{13}{10}x+\frac{169}{400}=\frac{1089}{400}
Add \frac{23}{10} to \frac{169}{400} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(x+\frac{13}{20}\right)^{2}=\frac{1089}{400}
Factor x^{2}+\frac{13}{10}x+\frac{169}{400}. 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{13}{20}\right)^{2}}=\sqrt{\frac{1089}{400}}
Take the square root of both sides of the equation.
x+\frac{13}{20}=\frac{33}{20} x+\frac{13}{20}=-\frac{33}{20}
Simplify.
x=1 x=-\frac{23}{10}
Subtract \frac{13}{20} from both sides of the equation.
Examples
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{ x } ^ { 2 } - 4 x - 5 = 0
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Linear equation
y = 3x + 4
Arithmetic
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Matrix
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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
\int _ { 0 } ^ { 1 } x e ^ { - x ^ { 2 } } d x
Limits
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