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\left(x+2\right)\left(x+1\right)+\left(2x+5\right)\times 3=0
Variable x cannot be equal to any of the values -\frac{5}{2},-2,1 since division by zero is not defined. Multiply both sides of the equation by \left(x-1\right)\left(x+2\right)\left(2x+5\right), the least common multiple of 2x^{2}+3x-5,x^{2}+x-2.
x^{2}+3x+2+\left(2x+5\right)\times 3=0
Use the distributive property to multiply x+2 by x+1 and combine like terms.
x^{2}+3x+2+6x+15=0
Use the distributive property to multiply 2x+5 by 3.
x^{2}+9x+2+15=0
Combine 3x and 6x to get 9x.
x^{2}+9x+17=0
Add 2 and 15 to get 17.
x=\frac{-9±\sqrt{9^{2}-4\times 17}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, 9 for b, and 17 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-9±\sqrt{81-4\times 17}}{2}
Square 9.
x=\frac{-9±\sqrt{81-68}}{2}
Multiply -4 times 17.
x=\frac{-9±\sqrt{13}}{2}
Add 81 to -68.
x=\frac{\sqrt{13}-9}{2}
Now solve the equation x=\frac{-9±\sqrt{13}}{2} when ± is plus. Add -9 to \sqrt{13}.
x=\frac{-\sqrt{13}-9}{2}
Now solve the equation x=\frac{-9±\sqrt{13}}{2} when ± is minus. Subtract \sqrt{13} from -9.
x=\frac{\sqrt{13}-9}{2} x=\frac{-\sqrt{13}-9}{2}
The equation is now solved.
\left(x+2\right)\left(x+1\right)+\left(2x+5\right)\times 3=0
Variable x cannot be equal to any of the values -\frac{5}{2},-2,1 since division by zero is not defined. Multiply both sides of the equation by \left(x-1\right)\left(x+2\right)\left(2x+5\right), the least common multiple of 2x^{2}+3x-5,x^{2}+x-2.
x^{2}+3x+2+\left(2x+5\right)\times 3=0
Use the distributive property to multiply x+2 by x+1 and combine like terms.
x^{2}+3x+2+6x+15=0
Use the distributive property to multiply 2x+5 by 3.
x^{2}+9x+2+15=0
Combine 3x and 6x to get 9x.
x^{2}+9x+17=0
Add 2 and 15 to get 17.
x^{2}+9x=-17
Subtract 17 from both sides. Anything subtracted from zero gives its negation.
x^{2}+9x+\left(\frac{9}{2}\right)^{2}=-17+\left(\frac{9}{2}\right)^{2}
Divide 9, the coefficient of the x term, by 2 to get \frac{9}{2}. Then add the square of \frac{9}{2} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+9x+\frac{81}{4}=-17+\frac{81}{4}
Square \frac{9}{2} by squaring both the numerator and the denominator of the fraction.
x^{2}+9x+\frac{81}{4}=\frac{13}{4}
Add -17 to \frac{81}{4}.
\left(x+\frac{9}{2}\right)^{2}=\frac{13}{4}
Factor x^{2}+9x+\frac{81}{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{9}{2}\right)^{2}}=\sqrt{\frac{13}{4}}
Take the square root of both sides of the equation.
x+\frac{9}{2}=\frac{\sqrt{13}}{2} x+\frac{9}{2}=-\frac{\sqrt{13}}{2}
Simplify.
x=\frac{\sqrt{13}-9}{2} x=\frac{-\sqrt{13}-9}{2}
Subtract \frac{9}{2} from both sides of the equation.