Solve for x
x = \frac{\sqrt{149} + 13}{2} \approx 12.603277808
x=\frac{13-\sqrt{149}}{2}\approx 0.396722192
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3\left(x-3\right)^{2}+5x+6=2\left(x+2\right)\left(x-2\right)+36
Multiply both sides of the equation by 6, the least common multiple of 2,6,3.
3\left(x^{2}-6x+9\right)+5x+6=2\left(x+2\right)\left(x-2\right)+36
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(x-3\right)^{2}.
3x^{2}-18x+27+5x+6=2\left(x+2\right)\left(x-2\right)+36
Use the distributive property to multiply 3 by x^{2}-6x+9.
3x^{2}-13x+27+6=2\left(x+2\right)\left(x-2\right)+36
Combine -18x and 5x to get -13x.
3x^{2}-13x+33=2\left(x+2\right)\left(x-2\right)+36
Add 27 and 6 to get 33.
3x^{2}-13x+33=\left(2x+4\right)\left(x-2\right)+36
Use the distributive property to multiply 2 by x+2.
3x^{2}-13x+33=2x^{2}-8+36
Use the distributive property to multiply 2x+4 by x-2 and combine like terms.
3x^{2}-13x+33=2x^{2}+28
Add -8 and 36 to get 28.
3x^{2}-13x+33-2x^{2}=28
Subtract 2x^{2} from both sides.
x^{2}-13x+33=28
Combine 3x^{2} and -2x^{2} to get x^{2}.
x^{2}-13x+33-28=0
Subtract 28 from both sides.
x^{2}-13x+5=0
Subtract 28 from 33 to get 5.
x=\frac{-\left(-13\right)±\sqrt{\left(-13\right)^{2}-4\times 5}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, -13 for b, and 5 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-13\right)±\sqrt{169-4\times 5}}{2}
Square -13.
x=\frac{-\left(-13\right)±\sqrt{169-20}}{2}
Multiply -4 times 5.
x=\frac{-\left(-13\right)±\sqrt{149}}{2}
Add 169 to -20.
x=\frac{13±\sqrt{149}}{2}
The opposite of -13 is 13.
x=\frac{\sqrt{149}+13}{2}
Now solve the equation x=\frac{13±\sqrt{149}}{2} when ± is plus. Add 13 to \sqrt{149}.
x=\frac{13-\sqrt{149}}{2}
Now solve the equation x=\frac{13±\sqrt{149}}{2} when ± is minus. Subtract \sqrt{149} from 13.
x=\frac{\sqrt{149}+13}{2} x=\frac{13-\sqrt{149}}{2}
The equation is now solved.
3\left(x-3\right)^{2}+5x+6=2\left(x+2\right)\left(x-2\right)+36
Multiply both sides of the equation by 6, the least common multiple of 2,6,3.
3\left(x^{2}-6x+9\right)+5x+6=2\left(x+2\right)\left(x-2\right)+36
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(x-3\right)^{2}.
3x^{2}-18x+27+5x+6=2\left(x+2\right)\left(x-2\right)+36
Use the distributive property to multiply 3 by x^{2}-6x+9.
3x^{2}-13x+27+6=2\left(x+2\right)\left(x-2\right)+36
Combine -18x and 5x to get -13x.
3x^{2}-13x+33=2\left(x+2\right)\left(x-2\right)+36
Add 27 and 6 to get 33.
3x^{2}-13x+33=\left(2x+4\right)\left(x-2\right)+36
Use the distributive property to multiply 2 by x+2.
3x^{2}-13x+33=2x^{2}-8+36
Use the distributive property to multiply 2x+4 by x-2 and combine like terms.
3x^{2}-13x+33=2x^{2}+28
Add -8 and 36 to get 28.
3x^{2}-13x+33-2x^{2}=28
Subtract 2x^{2} from both sides.
x^{2}-13x+33=28
Combine 3x^{2} and -2x^{2} to get x^{2}.
x^{2}-13x=28-33
Subtract 33 from both sides.
x^{2}-13x=-5
Subtract 33 from 28 to get -5.
x^{2}-13x+\left(-\frac{13}{2}\right)^{2}=-5+\left(-\frac{13}{2}\right)^{2}
Divide -13, the coefficient of the x term, by 2 to get -\frac{13}{2}. Then add the square of -\frac{13}{2} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-13x+\frac{169}{4}=-5+\frac{169}{4}
Square -\frac{13}{2} by squaring both the numerator and the denominator of the fraction.
x^{2}-13x+\frac{169}{4}=\frac{149}{4}
Add -5 to \frac{169}{4}.
\left(x-\frac{13}{2}\right)^{2}=\frac{149}{4}
Factor x^{2}-13x+\frac{169}{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{13}{2}\right)^{2}}=\sqrt{\frac{149}{4}}
Take the square root of both sides of the equation.
x-\frac{13}{2}=\frac{\sqrt{149}}{2} x-\frac{13}{2}=-\frac{\sqrt{149}}{2}
Simplify.
x=\frac{\sqrt{149}+13}{2} x=\frac{13-\sqrt{149}}{2}
Add \frac{13}{2} to both sides of the equation.
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Simultaneous equation
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Limits
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