Solve for X
X=5
X=-\frac{2}{3}\approx -0.666666667
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\left(4X+7\right)\left(X+3\right)-\left(2X-1\right)\left(5X-1\right)=0
Variable X cannot be equal to any of the values -\frac{7}{4},\frac{1}{2} since division by zero is not defined. Multiply both sides of the equation by \left(2X-1\right)\left(4X+7\right), the least common multiple of 2X-1,4X+7.
4X^{2}+19X+21-\left(2X-1\right)\left(5X-1\right)=0
Use the distributive property to multiply 4X+7 by X+3 and combine like terms.
4X^{2}+19X+21-\left(10X^{2}-7X+1\right)=0
Use the distributive property to multiply 2X-1 by 5X-1 and combine like terms.
4X^{2}+19X+21-10X^{2}+7X-1=0
To find the opposite of 10X^{2}-7X+1, find the opposite of each term.
-6X^{2}+19X+21+7X-1=0
Combine 4X^{2} and -10X^{2} to get -6X^{2}.
-6X^{2}+26X+21-1=0
Combine 19X and 7X to get 26X.
-6X^{2}+26X+20=0
Subtract 1 from 21 to get 20.
-3X^{2}+13X+10=0
Divide both sides by 2.
a+b=13 ab=-3\times 10=-30
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as -3X^{2}+aX+bX+10. To find a and b, set up a system to be solved.
-1,30 -2,15 -3,10 -5,6
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 -30.
-1+30=29 -2+15=13 -3+10=7 -5+6=1
Calculate the sum for each pair.
a=15 b=-2
The solution is the pair that gives sum 13.
\left(-3X^{2}+15X\right)+\left(-2X+10\right)
Rewrite -3X^{2}+13X+10 as \left(-3X^{2}+15X\right)+\left(-2X+10\right).
3X\left(-X+5\right)+2\left(-X+5\right)
Factor out 3X in the first and 2 in the second group.
\left(-X+5\right)\left(3X+2\right)
Factor out common term -X+5 by using distributive property.
X=5 X=-\frac{2}{3}
To find equation solutions, solve -X+5=0 and 3X+2=0.
\left(4X+7\right)\left(X+3\right)-\left(2X-1\right)\left(5X-1\right)=0
Variable X cannot be equal to any of the values -\frac{7}{4},\frac{1}{2} since division by zero is not defined. Multiply both sides of the equation by \left(2X-1\right)\left(4X+7\right), the least common multiple of 2X-1,4X+7.
4X^{2}+19X+21-\left(2X-1\right)\left(5X-1\right)=0
Use the distributive property to multiply 4X+7 by X+3 and combine like terms.
4X^{2}+19X+21-\left(10X^{2}-7X+1\right)=0
Use the distributive property to multiply 2X-1 by 5X-1 and combine like terms.
4X^{2}+19X+21-10X^{2}+7X-1=0
To find the opposite of 10X^{2}-7X+1, find the opposite of each term.
-6X^{2}+19X+21+7X-1=0
Combine 4X^{2} and -10X^{2} to get -6X^{2}.
-6X^{2}+26X+21-1=0
Combine 19X and 7X to get 26X.
-6X^{2}+26X+20=0
Subtract 1 from 21 to get 20.
X=\frac{-26±\sqrt{26^{2}-4\left(-6\right)\times 20}}{2\left(-6\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -6 for a, 26 for b, and 20 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
X=\frac{-26±\sqrt{676-4\left(-6\right)\times 20}}{2\left(-6\right)}
Square 26.
X=\frac{-26±\sqrt{676+24\times 20}}{2\left(-6\right)}
Multiply -4 times -6.
X=\frac{-26±\sqrt{676+480}}{2\left(-6\right)}
Multiply 24 times 20.
X=\frac{-26±\sqrt{1156}}{2\left(-6\right)}
Add 676 to 480.
X=\frac{-26±34}{2\left(-6\right)}
Take the square root of 1156.
X=\frac{-26±34}{-12}
Multiply 2 times -6.
X=\frac{8}{-12}
Now solve the equation X=\frac{-26±34}{-12} when ± is plus. Add -26 to 34.
X=-\frac{2}{3}
Reduce the fraction \frac{8}{-12} to lowest terms by extracting and canceling out 4.
X=-\frac{60}{-12}
Now solve the equation X=\frac{-26±34}{-12} when ± is minus. Subtract 34 from -26.
X=5
Divide -60 by -12.
X=-\frac{2}{3} X=5
The equation is now solved.
\left(4X+7\right)\left(X+3\right)-\left(2X-1\right)\left(5X-1\right)=0
Variable X cannot be equal to any of the values -\frac{7}{4},\frac{1}{2} since division by zero is not defined. Multiply both sides of the equation by \left(2X-1\right)\left(4X+7\right), the least common multiple of 2X-1,4X+7.
4X^{2}+19X+21-\left(2X-1\right)\left(5X-1\right)=0
Use the distributive property to multiply 4X+7 by X+3 and combine like terms.
4X^{2}+19X+21-\left(10X^{2}-7X+1\right)=0
Use the distributive property to multiply 2X-1 by 5X-1 and combine like terms.
4X^{2}+19X+21-10X^{2}+7X-1=0
To find the opposite of 10X^{2}-7X+1, find the opposite of each term.
-6X^{2}+19X+21+7X-1=0
Combine 4X^{2} and -10X^{2} to get -6X^{2}.
-6X^{2}+26X+21-1=0
Combine 19X and 7X to get 26X.
-6X^{2}+26X+20=0
Subtract 1 from 21 to get 20.
-6X^{2}+26X=-20
Subtract 20 from both sides. Anything subtracted from zero gives its negation.
\frac{-6X^{2}+26X}{-6}=-\frac{20}{-6}
Divide both sides by -6.
X^{2}+\frac{26}{-6}X=-\frac{20}{-6}
Dividing by -6 undoes the multiplication by -6.
X^{2}-\frac{13}{3}X=-\frac{20}{-6}
Reduce the fraction \frac{26}{-6} to lowest terms by extracting and canceling out 2.
X^{2}-\frac{13}{3}X=\frac{10}{3}
Reduce the fraction \frac{-20}{-6} to lowest terms by extracting and canceling out 2.
X^{2}-\frac{13}{3}X+\left(-\frac{13}{6}\right)^{2}=\frac{10}{3}+\left(-\frac{13}{6}\right)^{2}
Divide -\frac{13}{3}, the coefficient of the x term, by 2 to get -\frac{13}{6}. Then add the square of -\frac{13}{6} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
X^{2}-\frac{13}{3}X+\frac{169}{36}=\frac{10}{3}+\frac{169}{36}
Square -\frac{13}{6} by squaring both the numerator and the denominator of the fraction.
X^{2}-\frac{13}{3}X+\frac{169}{36}=\frac{289}{36}
Add \frac{10}{3} to \frac{169}{36} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(X-\frac{13}{6}\right)^{2}=\frac{289}{36}
Factor X^{2}-\frac{13}{3}X+\frac{169}{36}. 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}{6}\right)^{2}}=\sqrt{\frac{289}{36}}
Take the square root of both sides of the equation.
X-\frac{13}{6}=\frac{17}{6} X-\frac{13}{6}=-\frac{17}{6}
Simplify.
X=5 X=-\frac{2}{3}
Add \frac{13}{6} to both sides of the equation.
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Limits
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