Solve for x
x=8
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\left(x-2\right)\left(x+2\right)-\left(x+2\right)\times 5=x+2
Variable x cannot be equal to any of the values -2,2 since division by zero is not defined. Multiply both sides of the equation by \left(x-2\right)\left(x+2\right), the least common multiple of x-2,x^{2}-4.
x^{2}-4-\left(x+2\right)\times 5=x+2
Consider \left(x-2\right)\left(x+2\right). Multiplication can be transformed into difference of squares using the rule: \left(a-b\right)\left(a+b\right)=a^{2}-b^{2}. Square 2.
x^{2}-4-\left(5x+10\right)=x+2
Use the distributive property to multiply x+2 by 5.
x^{2}-4-5x-10=x+2
To find the opposite of 5x+10, find the opposite of each term.
x^{2}-14-5x=x+2
Subtract 10 from -4 to get -14.
x^{2}-14-5x-x=2
Subtract x from both sides.
x^{2}-14-6x=2
Combine -5x and -x to get -6x.
x^{2}-14-6x-2=0
Subtract 2 from both sides.
x^{2}-16-6x=0
Subtract 2 from -14 to get -16.
x^{2}-6x-16=0
Rearrange the polynomial to put it in standard form. Place the terms in order from highest to lowest power.
a+b=-6 ab=-16
To solve the equation, factor x^{2}-6x-16 using formula x^{2}+\left(a+b\right)x+ab=\left(x+a\right)\left(x+b\right). To find a and b, set up a system to be solved.
1,-16 2,-8 4,-4
Since ab is negative, a and b have the opposite signs. Since a+b is negative, the negative number has greater absolute value than the positive. List all such integer pairs that give product -16.
1-16=-15 2-8=-6 4-4=0
Calculate the sum for each pair.
a=-8 b=2
The solution is the pair that gives sum -6.
\left(x-8\right)\left(x+2\right)
Rewrite factored expression \left(x+a\right)\left(x+b\right) using the obtained values.
x=8 x=-2
To find equation solutions, solve x-8=0 and x+2=0.
x=8
Variable x cannot be equal to -2.
\left(x-2\right)\left(x+2\right)-\left(x+2\right)\times 5=x+2
Variable x cannot be equal to any of the values -2,2 since division by zero is not defined. Multiply both sides of the equation by \left(x-2\right)\left(x+2\right), the least common multiple of x-2,x^{2}-4.
x^{2}-4-\left(x+2\right)\times 5=x+2
Consider \left(x-2\right)\left(x+2\right). Multiplication can be transformed into difference of squares using the rule: \left(a-b\right)\left(a+b\right)=a^{2}-b^{2}. Square 2.
x^{2}-4-\left(5x+10\right)=x+2
Use the distributive property to multiply x+2 by 5.
x^{2}-4-5x-10=x+2
To find the opposite of 5x+10, find the opposite of each term.
x^{2}-14-5x=x+2
Subtract 10 from -4 to get -14.
x^{2}-14-5x-x=2
Subtract x from both sides.
x^{2}-14-6x=2
Combine -5x and -x to get -6x.
x^{2}-14-6x-2=0
Subtract 2 from both sides.
x^{2}-16-6x=0
Subtract 2 from -14 to get -16.
x^{2}-6x-16=0
Rearrange the polynomial to put it in standard form. Place the terms in order from highest to lowest power.
a+b=-6 ab=1\left(-16\right)=-16
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as x^{2}+ax+bx-16. To find a and b, set up a system to be solved.
1,-16 2,-8 4,-4
Since ab is negative, a and b have the opposite signs. Since a+b is negative, the negative number has greater absolute value than the positive. List all such integer pairs that give product -16.
1-16=-15 2-8=-6 4-4=0
Calculate the sum for each pair.
a=-8 b=2
The solution is the pair that gives sum -6.
\left(x^{2}-8x\right)+\left(2x-16\right)
Rewrite x^{2}-6x-16 as \left(x^{2}-8x\right)+\left(2x-16\right).
x\left(x-8\right)+2\left(x-8\right)
Factor out x in the first and 2 in the second group.
\left(x-8\right)\left(x+2\right)
Factor out common term x-8 by using distributive property.
x=8 x=-2
To find equation solutions, solve x-8=0 and x+2=0.
x=8
Variable x cannot be equal to -2.
\left(x-2\right)\left(x+2\right)-\left(x+2\right)\times 5=x+2
Variable x cannot be equal to any of the values -2,2 since division by zero is not defined. Multiply both sides of the equation by \left(x-2\right)\left(x+2\right), the least common multiple of x-2,x^{2}-4.
x^{2}-4-\left(x+2\right)\times 5=x+2
Consider \left(x-2\right)\left(x+2\right). Multiplication can be transformed into difference of squares using the rule: \left(a-b\right)\left(a+b\right)=a^{2}-b^{2}. Square 2.
x^{2}-4-\left(5x+10\right)=x+2
Use the distributive property to multiply x+2 by 5.
x^{2}-4-5x-10=x+2
To find the opposite of 5x+10, find the opposite of each term.
x^{2}-14-5x=x+2
Subtract 10 from -4 to get -14.
x^{2}-14-5x-x=2
Subtract x from both sides.
x^{2}-14-6x=2
Combine -5x and -x to get -6x.
x^{2}-14-6x-2=0
Subtract 2 from both sides.
x^{2}-16-6x=0
Subtract 2 from -14 to get -16.
x^{2}-6x-16=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(-6\right)±\sqrt{\left(-6\right)^{2}-4\left(-16\right)}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, -6 for b, and -16 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-6\right)±\sqrt{36-4\left(-16\right)}}{2}
Square -6.
x=\frac{-\left(-6\right)±\sqrt{36+64}}{2}
Multiply -4 times -16.
x=\frac{-\left(-6\right)±\sqrt{100}}{2}
Add 36 to 64.
x=\frac{-\left(-6\right)±10}{2}
Take the square root of 100.
x=\frac{6±10}{2}
The opposite of -6 is 6.
x=\frac{16}{2}
Now solve the equation x=\frac{6±10}{2} when ± is plus. Add 6 to 10.
x=8
Divide 16 by 2.
x=-\frac{4}{2}
Now solve the equation x=\frac{6±10}{2} when ± is minus. Subtract 10 from 6.
x=-2
Divide -4 by 2.
x=8 x=-2
The equation is now solved.
x=8
Variable x cannot be equal to -2.
\left(x-2\right)\left(x+2\right)-\left(x+2\right)\times 5=x+2
Variable x cannot be equal to any of the values -2,2 since division by zero is not defined. Multiply both sides of the equation by \left(x-2\right)\left(x+2\right), the least common multiple of x-2,x^{2}-4.
x^{2}-4-\left(x+2\right)\times 5=x+2
Consider \left(x-2\right)\left(x+2\right). Multiplication can be transformed into difference of squares using the rule: \left(a-b\right)\left(a+b\right)=a^{2}-b^{2}. Square 2.
x^{2}-4-\left(5x+10\right)=x+2
Use the distributive property to multiply x+2 by 5.
x^{2}-4-5x-10=x+2
To find the opposite of 5x+10, find the opposite of each term.
x^{2}-14-5x=x+2
Subtract 10 from -4 to get -14.
x^{2}-14-5x-x=2
Subtract x from both sides.
x^{2}-14-6x=2
Combine -5x and -x to get -6x.
x^{2}-6x=2+14
Add 14 to both sides.
x^{2}-6x=16
Add 2 and 14 to get 16.
x^{2}-6x+\left(-3\right)^{2}=16+\left(-3\right)^{2}
Divide -6, the coefficient of the x term, by 2 to get -3. Then add the square of -3 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-6x+9=16+9
Square -3.
x^{2}-6x+9=25
Add 16 to 9.
\left(x-3\right)^{2}=25
Factor x^{2}-6x+9. 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-3\right)^{2}}=\sqrt{25}
Take the square root of both sides of the equation.
x-3=5 x-3=-5
Simplify.
x=8 x=-2
Add 3 to both sides of the equation.
x=8
Variable x cannot be equal to -2.
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