Solve for x
x = -\frac{16}{7} = -2\frac{2}{7} \approx -2.285714286
x=3
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\left(6x-12\right)\left(x+2\right)+\left(6x+18\right)\left(x-3\right)=5\left(x-2\right)\left(x+3\right)
Variable x cannot be equal to any of the values -3,2 since division by zero is not defined. Multiply both sides of the equation by 6\left(x-2\right)\left(x+3\right), the least common multiple of x+3,x-2,6.
6x^{2}-24+\left(6x+18\right)\left(x-3\right)=5\left(x-2\right)\left(x+3\right)
Use the distributive property to multiply 6x-12 by x+2 and combine like terms.
6x^{2}-24+6x^{2}-54=5\left(x-2\right)\left(x+3\right)
Use the distributive property to multiply 6x+18 by x-3 and combine like terms.
12x^{2}-24-54=5\left(x-2\right)\left(x+3\right)
Combine 6x^{2} and 6x^{2} to get 12x^{2}.
12x^{2}-78=5\left(x-2\right)\left(x+3\right)
Subtract 54 from -24 to get -78.
12x^{2}-78=\left(5x-10\right)\left(x+3\right)
Use the distributive property to multiply 5 by x-2.
12x^{2}-78=5x^{2}+5x-30
Use the distributive property to multiply 5x-10 by x+3 and combine like terms.
12x^{2}-78-5x^{2}=5x-30
Subtract 5x^{2} from both sides.
7x^{2}-78=5x-30
Combine 12x^{2} and -5x^{2} to get 7x^{2}.
7x^{2}-78-5x=-30
Subtract 5x from both sides.
7x^{2}-78-5x+30=0
Add 30 to both sides.
7x^{2}-48-5x=0
Add -78 and 30 to get -48.
7x^{2}-5x-48=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{-\left(-5\right)±\sqrt{\left(-5\right)^{2}-4\times 7\left(-48\right)}}{2\times 7}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 7 for a, -5 for b, and -48 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-5\right)±\sqrt{25-4\times 7\left(-48\right)}}{2\times 7}
Square -5.
x=\frac{-\left(-5\right)±\sqrt{25-28\left(-48\right)}}{2\times 7}
Multiply -4 times 7.
x=\frac{-\left(-5\right)±\sqrt{25+1344}}{2\times 7}
Multiply -28 times -48.
x=\frac{-\left(-5\right)±\sqrt{1369}}{2\times 7}
Add 25 to 1344.
x=\frac{-\left(-5\right)±37}{2\times 7}
Take the square root of 1369.
x=\frac{5±37}{2\times 7}
The opposite of -5 is 5.
x=\frac{5±37}{14}
Multiply 2 times 7.
x=\frac{42}{14}
Now solve the equation x=\frac{5±37}{14} when ± is plus. Add 5 to 37.
x=3
Divide 42 by 14.
x=-\frac{32}{14}
Now solve the equation x=\frac{5±37}{14} when ± is minus. Subtract 37 from 5.
x=-\frac{16}{7}
Reduce the fraction \frac{-32}{14} to lowest terms by extracting and canceling out 2.
x=3 x=-\frac{16}{7}
The equation is now solved.
\left(6x-12\right)\left(x+2\right)+\left(6x+18\right)\left(x-3\right)=5\left(x-2\right)\left(x+3\right)
Variable x cannot be equal to any of the values -3,2 since division by zero is not defined. Multiply both sides of the equation by 6\left(x-2\right)\left(x+3\right), the least common multiple of x+3,x-2,6.
6x^{2}-24+\left(6x+18\right)\left(x-3\right)=5\left(x-2\right)\left(x+3\right)
Use the distributive property to multiply 6x-12 by x+2 and combine like terms.
6x^{2}-24+6x^{2}-54=5\left(x-2\right)\left(x+3\right)
Use the distributive property to multiply 6x+18 by x-3 and combine like terms.
12x^{2}-24-54=5\left(x-2\right)\left(x+3\right)
Combine 6x^{2} and 6x^{2} to get 12x^{2}.
12x^{2}-78=5\left(x-2\right)\left(x+3\right)
Subtract 54 from -24 to get -78.
12x^{2}-78=\left(5x-10\right)\left(x+3\right)
Use the distributive property to multiply 5 by x-2.
12x^{2}-78=5x^{2}+5x-30
Use the distributive property to multiply 5x-10 by x+3 and combine like terms.
12x^{2}-78-5x^{2}=5x-30
Subtract 5x^{2} from both sides.
7x^{2}-78=5x-30
Combine 12x^{2} and -5x^{2} to get 7x^{2}.
7x^{2}-78-5x=-30
Subtract 5x from both sides.
7x^{2}-5x=-30+78
Add 78 to both sides.
7x^{2}-5x=48
Add -30 and 78 to get 48.
\frac{7x^{2}-5x}{7}=\frac{48}{7}
Divide both sides by 7.
x^{2}-\frac{5}{7}x=\frac{48}{7}
Dividing by 7 undoes the multiplication by 7.
x^{2}-\frac{5}{7}x+\left(-\frac{5}{14}\right)^{2}=\frac{48}{7}+\left(-\frac{5}{14}\right)^{2}
Divide -\frac{5}{7}, the coefficient of the x term, by 2 to get -\frac{5}{14}. Then add the square of -\frac{5}{14} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-\frac{5}{7}x+\frac{25}{196}=\frac{48}{7}+\frac{25}{196}
Square -\frac{5}{14} by squaring both the numerator and the denominator of the fraction.
x^{2}-\frac{5}{7}x+\frac{25}{196}=\frac{1369}{196}
Add \frac{48}{7} to \frac{25}{196} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(x-\frac{5}{14}\right)^{2}=\frac{1369}{196}
Factor x^{2}-\frac{5}{7}x+\frac{25}{196}. 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}{14}\right)^{2}}=\sqrt{\frac{1369}{196}}
Take the square root of both sides of the equation.
x-\frac{5}{14}=\frac{37}{14} x-\frac{5}{14}=-\frac{37}{14}
Simplify.
x=3 x=-\frac{16}{7}
Add \frac{5}{14} to both sides of the equation.
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