Solve for x
x=-3
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\left(x-5\right)\left(x+4\right)-\left(x+2\right)\left(2x-3\right)=3x-8
Variable x cannot be equal to any of the values -2,5 since division by zero is not defined. Multiply both sides of the equation by \left(x-5\right)\left(x+2\right), the least common multiple of x+2,x-5,x^{2}-3x-10.
x^{2}-x-20-\left(x+2\right)\left(2x-3\right)=3x-8
Use the distributive property to multiply x-5 by x+4 and combine like terms.
x^{2}-x-20-\left(2x^{2}+x-6\right)=3x-8
Use the distributive property to multiply x+2 by 2x-3 and combine like terms.
x^{2}-x-20-2x^{2}-x+6=3x-8
To find the opposite of 2x^{2}+x-6, find the opposite of each term.
-x^{2}-x-20-x+6=3x-8
Combine x^{2} and -2x^{2} to get -x^{2}.
-x^{2}-2x-20+6=3x-8
Combine -x and -x to get -2x.
-x^{2}-2x-14=3x-8
Add -20 and 6 to get -14.
-x^{2}-2x-14-3x=-8
Subtract 3x from both sides.
-x^{2}-5x-14=-8
Combine -2x and -3x to get -5x.
-x^{2}-5x-14+8=0
Add 8 to both sides.
-x^{2}-5x-6=0
Add -14 and 8 to get -6.
a+b=-5 ab=-\left(-6\right)=6
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as -x^{2}+ax+bx-6. To find a and b, set up a system to be solved.
-1,-6 -2,-3
Since ab is positive, a and b have the same sign. Since a+b is negative, a and b are both negative. List all such integer pairs that give product 6.
-1-6=-7 -2-3=-5
Calculate the sum for each pair.
a=-2 b=-3
The solution is the pair that gives sum -5.
\left(-x^{2}-2x\right)+\left(-3x-6\right)
Rewrite -x^{2}-5x-6 as \left(-x^{2}-2x\right)+\left(-3x-6\right).
x\left(-x-2\right)+3\left(-x-2\right)
Factor out x in the first and 3 in the second group.
\left(-x-2\right)\left(x+3\right)
Factor out common term -x-2 by using distributive property.
x=-2 x=-3
To find equation solutions, solve -x-2=0 and x+3=0.
x=-3
Variable x cannot be equal to -2.
\left(x-5\right)\left(x+4\right)-\left(x+2\right)\left(2x-3\right)=3x-8
Variable x cannot be equal to any of the values -2,5 since division by zero is not defined. Multiply both sides of the equation by \left(x-5\right)\left(x+2\right), the least common multiple of x+2,x-5,x^{2}-3x-10.
x^{2}-x-20-\left(x+2\right)\left(2x-3\right)=3x-8
Use the distributive property to multiply x-5 by x+4 and combine like terms.
x^{2}-x-20-\left(2x^{2}+x-6\right)=3x-8
Use the distributive property to multiply x+2 by 2x-3 and combine like terms.
x^{2}-x-20-2x^{2}-x+6=3x-8
To find the opposite of 2x^{2}+x-6, find the opposite of each term.
-x^{2}-x-20-x+6=3x-8
Combine x^{2} and -2x^{2} to get -x^{2}.
-x^{2}-2x-20+6=3x-8
Combine -x and -x to get -2x.
-x^{2}-2x-14=3x-8
Add -20 and 6 to get -14.
-x^{2}-2x-14-3x=-8
Subtract 3x from both sides.
-x^{2}-5x-14=-8
Combine -2x and -3x to get -5x.
-x^{2}-5x-14+8=0
Add 8 to both sides.
-x^{2}-5x-6=0
Add -14 and 8 to get -6.
x=\frac{-\left(-5\right)±\sqrt{\left(-5\right)^{2}-4\left(-1\right)\left(-6\right)}}{2\left(-1\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -1 for a, -5 for b, and -6 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-5\right)±\sqrt{25-4\left(-1\right)\left(-6\right)}}{2\left(-1\right)}
Square -5.
x=\frac{-\left(-5\right)±\sqrt{25+4\left(-6\right)}}{2\left(-1\right)}
Multiply -4 times -1.
x=\frac{-\left(-5\right)±\sqrt{25-24}}{2\left(-1\right)}
Multiply 4 times -6.
x=\frac{-\left(-5\right)±\sqrt{1}}{2\left(-1\right)}
Add 25 to -24.
x=\frac{-\left(-5\right)±1}{2\left(-1\right)}
Take the square root of 1.
x=\frac{5±1}{2\left(-1\right)}
The opposite of -5 is 5.
x=\frac{5±1}{-2}
Multiply 2 times -1.
x=\frac{6}{-2}
Now solve the equation x=\frac{5±1}{-2} when ± is plus. Add 5 to 1.
x=-3
Divide 6 by -2.
x=\frac{4}{-2}
Now solve the equation x=\frac{5±1}{-2} when ± is minus. Subtract 1 from 5.
x=-2
Divide 4 by -2.
x=-3 x=-2
The equation is now solved.
x=-3
Variable x cannot be equal to -2.
\left(x-5\right)\left(x+4\right)-\left(x+2\right)\left(2x-3\right)=3x-8
Variable x cannot be equal to any of the values -2,5 since division by zero is not defined. Multiply both sides of the equation by \left(x-5\right)\left(x+2\right), the least common multiple of x+2,x-5,x^{2}-3x-10.
x^{2}-x-20-\left(x+2\right)\left(2x-3\right)=3x-8
Use the distributive property to multiply x-5 by x+4 and combine like terms.
x^{2}-x-20-\left(2x^{2}+x-6\right)=3x-8
Use the distributive property to multiply x+2 by 2x-3 and combine like terms.
x^{2}-x-20-2x^{2}-x+6=3x-8
To find the opposite of 2x^{2}+x-6, find the opposite of each term.
-x^{2}-x-20-x+6=3x-8
Combine x^{2} and -2x^{2} to get -x^{2}.
-x^{2}-2x-20+6=3x-8
Combine -x and -x to get -2x.
-x^{2}-2x-14=3x-8
Add -20 and 6 to get -14.
-x^{2}-2x-14-3x=-8
Subtract 3x from both sides.
-x^{2}-5x-14=-8
Combine -2x and -3x to get -5x.
-x^{2}-5x=-8+14
Add 14 to both sides.
-x^{2}-5x=6
Add -8 and 14 to get 6.
\frac{-x^{2}-5x}{-1}=\frac{6}{-1}
Divide both sides by -1.
x^{2}+\left(-\frac{5}{-1}\right)x=\frac{6}{-1}
Dividing by -1 undoes the multiplication by -1.
x^{2}+5x=\frac{6}{-1}
Divide -5 by -1.
x^{2}+5x=-6
Divide 6 by -1.
x^{2}+5x+\left(\frac{5}{2}\right)^{2}=-6+\left(\frac{5}{2}\right)^{2}
Divide 5, the coefficient of the x term, by 2 to get \frac{5}{2}. Then add the square of \frac{5}{2} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+5x+\frac{25}{4}=-6+\frac{25}{4}
Square \frac{5}{2} by squaring both the numerator and the denominator of the fraction.
x^{2}+5x+\frac{25}{4}=\frac{1}{4}
Add -6 to \frac{25}{4}.
\left(x+\frac{5}{2}\right)^{2}=\frac{1}{4}
Factor x^{2}+5x+\frac{25}{4}. 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{5}{2}\right)^{2}}=\sqrt{\frac{1}{4}}
Take the square root of both sides of the equation.
x+\frac{5}{2}=\frac{1}{2} x+\frac{5}{2}=-\frac{1}{2}
Simplify.
x=-2 x=-3
Subtract \frac{5}{2} from both sides of the equation.
x=-3
Variable x cannot be equal to -2.
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