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x-3=2\left(x-3\right)\left(x-2\right)
Variable x cannot be equal to any of the values 2,3 since division by zero is not defined. Multiply both sides of the equation by \left(x-3\right)\left(x-2\right).
x-3=\left(2x-6\right)\left(x-2\right)
Use the distributive property to multiply 2 by x-3.
x-3=2x^{2}-10x+12
Use the distributive property to multiply 2x-6 by x-2 and combine like terms.
x-3-2x^{2}=-10x+12
Subtract 2x^{2} from both sides.
x-3-2x^{2}+10x=12
Add 10x to both sides.
11x-3-2x^{2}=12
Combine x and 10x to get 11x.
11x-3-2x^{2}-12=0
Subtract 12 from both sides.
11x-15-2x^{2}=0
Subtract 12 from -3 to get -15.
-2x^{2}+11x-15=0
Rearrange the polynomial to put it in standard form. Place the terms in order from highest to lowest power.
a+b=11 ab=-2\left(-15\right)=30
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as -2x^{2}+ax+bx-15. To find a and b, set up a system to be solved.
1,30 2,15 3,10 5,6
Since ab is positive, a and b have the same sign. Since a+b is positive, a and b are both positive. List all such integer pairs that give product 30.
1+30=31 2+15=17 3+10=13 5+6=11
Calculate the sum for each pair.
a=6 b=5
The solution is the pair that gives sum 11.
\left(-2x^{2}+6x\right)+\left(5x-15\right)
Rewrite -2x^{2}+11x-15 as \left(-2x^{2}+6x\right)+\left(5x-15\right).
2x\left(-x+3\right)-5\left(-x+3\right)
Factor out 2x in the first and -5 in the second group.
\left(-x+3\right)\left(2x-5\right)
Factor out common term -x+3 by using distributive property.
x=3 x=\frac{5}{2}
To find equation solutions, solve -x+3=0 and 2x-5=0.
x=\frac{5}{2}
Variable x cannot be equal to 3.
x-3=2\left(x-3\right)\left(x-2\right)
Variable x cannot be equal to any of the values 2,3 since division by zero is not defined. Multiply both sides of the equation by \left(x-3\right)\left(x-2\right).
x-3=\left(2x-6\right)\left(x-2\right)
Use the distributive property to multiply 2 by x-3.
x-3=2x^{2}-10x+12
Use the distributive property to multiply 2x-6 by x-2 and combine like terms.
x-3-2x^{2}=-10x+12
Subtract 2x^{2} from both sides.
x-3-2x^{2}+10x=12
Add 10x to both sides.
11x-3-2x^{2}=12
Combine x and 10x to get 11x.
11x-3-2x^{2}-12=0
Subtract 12 from both sides.
11x-15-2x^{2}=0
Subtract 12 from -3 to get -15.
-2x^{2}+11x-15=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{-11±\sqrt{11^{2}-4\left(-2\right)\left(-15\right)}}{2\left(-2\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -2 for a, 11 for b, and -15 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-11±\sqrt{121-4\left(-2\right)\left(-15\right)}}{2\left(-2\right)}
Square 11.
x=\frac{-11±\sqrt{121+8\left(-15\right)}}{2\left(-2\right)}
Multiply -4 times -2.
x=\frac{-11±\sqrt{121-120}}{2\left(-2\right)}
Multiply 8 times -15.
x=\frac{-11±\sqrt{1}}{2\left(-2\right)}
Add 121 to -120.
x=\frac{-11±1}{2\left(-2\right)}
Take the square root of 1.
x=\frac{-11±1}{-4}
Multiply 2 times -2.
x=-\frac{10}{-4}
Now solve the equation x=\frac{-11±1}{-4} when ± is plus. Add -11 to 1.
x=\frac{5}{2}
Reduce the fraction \frac{-10}{-4} to lowest terms by extracting and canceling out 2.
x=-\frac{12}{-4}
Now solve the equation x=\frac{-11±1}{-4} when ± is minus. Subtract 1 from -11.
x=3
Divide -12 by -4.
x=\frac{5}{2} x=3
The equation is now solved.
x=\frac{5}{2}
Variable x cannot be equal to 3.
x-3=2\left(x-3\right)\left(x-2\right)
Variable x cannot be equal to any of the values 2,3 since division by zero is not defined. Multiply both sides of the equation by \left(x-3\right)\left(x-2\right).
x-3=\left(2x-6\right)\left(x-2\right)
Use the distributive property to multiply 2 by x-3.
x-3=2x^{2}-10x+12
Use the distributive property to multiply 2x-6 by x-2 and combine like terms.
x-3-2x^{2}=-10x+12
Subtract 2x^{2} from both sides.
x-3-2x^{2}+10x=12
Add 10x to both sides.
11x-3-2x^{2}=12
Combine x and 10x to get 11x.
11x-2x^{2}=12+3
Add 3 to both sides.
11x-2x^{2}=15
Add 12 and 3 to get 15.
-2x^{2}+11x=15
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{-2x^{2}+11x}{-2}=\frac{15}{-2}
Divide both sides by -2.
x^{2}+\frac{11}{-2}x=\frac{15}{-2}
Dividing by -2 undoes the multiplication by -2.
x^{2}-\frac{11}{2}x=\frac{15}{-2}
Divide 11 by -2.
x^{2}-\frac{11}{2}x=-\frac{15}{2}
Divide 15 by -2.
x^{2}-\frac{11}{2}x+\left(-\frac{11}{4}\right)^{2}=-\frac{15}{2}+\left(-\frac{11}{4}\right)^{2}
Divide -\frac{11}{2}, the coefficient of the x term, by 2 to get -\frac{11}{4}. Then add the square of -\frac{11}{4} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-\frac{11}{2}x+\frac{121}{16}=-\frac{15}{2}+\frac{121}{16}
Square -\frac{11}{4} by squaring both the numerator and the denominator of the fraction.
x^{2}-\frac{11}{2}x+\frac{121}{16}=\frac{1}{16}
Add -\frac{15}{2} to \frac{121}{16} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(x-\frac{11}{4}\right)^{2}=\frac{1}{16}
Factor x^{2}-\frac{11}{2}x+\frac{121}{16}. 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{11}{4}\right)^{2}}=\sqrt{\frac{1}{16}}
Take the square root of both sides of the equation.
x-\frac{11}{4}=\frac{1}{4} x-\frac{11}{4}=-\frac{1}{4}
Simplify.
x=3 x=\frac{5}{2}
Add \frac{11}{4} to both sides of the equation.
x=\frac{5}{2}
Variable x cannot be equal to 3.