Solve for x
x=-9
x=3
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\left(x-2\right)\times 5+\left(x-5\right)x=-6x+17
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-5,x-2,\left(x-5\right)\left(x-2\right).
5x-10+\left(x-5\right)x=-6x+17
Use the distributive property to multiply x-2 by 5.
5x-10+x^{2}-5x=-6x+17
Use the distributive property to multiply x-5 by x.
-10+x^{2}=-6x+17
Combine 5x and -5x to get 0.
-10+x^{2}+6x=17
Add 6x to both sides.
-10+x^{2}+6x-17=0
Subtract 17 from both sides.
-27+x^{2}+6x=0
Subtract 17 from -10 to get -27.
x^{2}+6x-27=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{-6±\sqrt{6^{2}-4\left(-27\right)}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, 6 for b, and -27 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-6±\sqrt{36-4\left(-27\right)}}{2}
Square 6.
x=\frac{-6±\sqrt{36+108}}{2}
Multiply -4 times -27.
x=\frac{-6±\sqrt{144}}{2}
Add 36 to 108.
x=\frac{-6±12}{2}
Take the square root of 144.
x=\frac{6}{2}
Now solve the equation x=\frac{-6±12}{2} when ± is plus. Add -6 to 12.
x=3
Divide 6 by 2.
x=-\frac{18}{2}
Now solve the equation x=\frac{-6±12}{2} when ± is minus. Subtract 12 from -6.
x=-9
Divide -18 by 2.
x=3 x=-9
The equation is now solved.
\left(x-2\right)\times 5+\left(x-5\right)x=-6x+17
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-5,x-2,\left(x-5\right)\left(x-2\right).
5x-10+\left(x-5\right)x=-6x+17
Use the distributive property to multiply x-2 by 5.
5x-10+x^{2}-5x=-6x+17
Use the distributive property to multiply x-5 by x.
-10+x^{2}=-6x+17
Combine 5x and -5x to get 0.
-10+x^{2}+6x=17
Add 6x to both sides.
x^{2}+6x=17+10
Add 10 to both sides.
x^{2}+6x=27
Add 17 and 10 to get 27.
x^{2}+6x+3^{2}=27+3^{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=27+9
Square 3.
x^{2}+6x+9=36
Add 27 to 9.
\left(x+3\right)^{2}=36
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{36}
Take the square root of both sides of the equation.
x+3=6 x+3=-6
Simplify.
x=3 x=-9
Subtract 3 from both sides of the equation.
Examples
Quadratic equation
{ x } ^ { 2 } - 4 x - 5 = 0
Trigonometry
4 \sin \theta \cos \theta = 2 \sin \theta
Linear equation
y = 3x + 4
Arithmetic
699 * 533
Matrix
\left[ \begin{array} { l l } { 2 } & { 3 } \\ { 5 } & { 4 } \end{array} \right] \left[ \begin{array} { l l l } { 2 } & { 0 } & { 3 } \\ { -1 } & { 1 } & { 5 } \end{array} \right]
Simultaneous equation
\left. \begin{cases} { 8x+2y = 46 } \\ { 7x+3y = 47 } \end{cases} \right.
Differentiation
\frac { d } { d x } \frac { ( 3 x ^ { 2 } - 2 ) } { ( x - 5 ) }
Integration
\int _ { 0 } ^ { 1 } x e ^ { - x ^ { 2 } } d x
Limits
\lim _{x \rightarrow-3} \frac{x^{2}-9}{x^{2}+2 x-3}