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2\left(x^{2}+5\right)+3x=24
Multiply both sides of the equation by 6, the least common multiple of 3,2.
2x^{2}+10+3x=24
Use the distributive property to multiply 2 by x^{2}+5.
2x^{2}+10+3x-24=0
Subtract 24 from both sides.
2x^{2}-14+3x=0
Subtract 24 from 10 to get -14.
2x^{2}+3x-14=0
Rearrange the polynomial to put it in standard form. Place the terms in order from highest to lowest power.
a+b=3 ab=2\left(-14\right)=-28
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as 2x^{2}+ax+bx-14. To find a and b, set up a system to be solved.
-1,28 -2,14 -4,7
Since ab is negative, a and b have the opposite signs. Since a+b is positive, the positive number has greater absolute value than the negative. List all such integer pairs that give product -28.
-1+28=27 -2+14=12 -4+7=3
Calculate the sum for each pair.
a=-4 b=7
The solution is the pair that gives sum 3.
\left(2x^{2}-4x\right)+\left(7x-14\right)
Rewrite 2x^{2}+3x-14 as \left(2x^{2}-4x\right)+\left(7x-14\right).
2x\left(x-2\right)+7\left(x-2\right)
Factor out 2x in the first and 7 in the second group.
\left(x-2\right)\left(2x+7\right)
Factor out common term x-2 by using distributive property.
x=2 x=-\frac{7}{2}
To find equation solutions, solve x-2=0 and 2x+7=0.
2\left(x^{2}+5\right)+3x=24
Multiply both sides of the equation by 6, the least common multiple of 3,2.
2x^{2}+10+3x=24
Use the distributive property to multiply 2 by x^{2}+5.
2x^{2}+10+3x-24=0
Subtract 24 from both sides.
2x^{2}-14+3x=0
Subtract 24 from 10 to get -14.
2x^{2}+3x-14=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{-3±\sqrt{3^{2}-4\times 2\left(-14\right)}}{2\times 2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 2 for a, 3 for b, and -14 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-3±\sqrt{9-4\times 2\left(-14\right)}}{2\times 2}
Square 3.
x=\frac{-3±\sqrt{9-8\left(-14\right)}}{2\times 2}
Multiply -4 times 2.
x=\frac{-3±\sqrt{9+112}}{2\times 2}
Multiply -8 times -14.
x=\frac{-3±\sqrt{121}}{2\times 2}
Add 9 to 112.
x=\frac{-3±11}{2\times 2}
Take the square root of 121.
x=\frac{-3±11}{4}
Multiply 2 times 2.
x=\frac{8}{4}
Now solve the equation x=\frac{-3±11}{4} when ± is plus. Add -3 to 11.
x=2
Divide 8 by 4.
x=-\frac{14}{4}
Now solve the equation x=\frac{-3±11}{4} when ± is minus. Subtract 11 from -3.
x=-\frac{7}{2}
Reduce the fraction \frac{-14}{4} to lowest terms by extracting and canceling out 2.
x=2 x=-\frac{7}{2}
The equation is now solved.
2\left(x^{2}+5\right)+3x=24
Multiply both sides of the equation by 6, the least common multiple of 3,2.
2x^{2}+10+3x=24
Use the distributive property to multiply 2 by x^{2}+5.
2x^{2}+3x=24-10
Subtract 10 from both sides.
2x^{2}+3x=14
Subtract 10 from 24 to get 14.
\frac{2x^{2}+3x}{2}=\frac{14}{2}
Divide both sides by 2.
x^{2}+\frac{3}{2}x=\frac{14}{2}
Dividing by 2 undoes the multiplication by 2.
x^{2}+\frac{3}{2}x=7
Divide 14 by 2.
x^{2}+\frac{3}{2}x+\left(\frac{3}{4}\right)^{2}=7+\left(\frac{3}{4}\right)^{2}
Divide \frac{3}{2}, the coefficient of the x term, by 2 to get \frac{3}{4}. Then add the square of \frac{3}{4} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+\frac{3}{2}x+\frac{9}{16}=7+\frac{9}{16}
Square \frac{3}{4} by squaring both the numerator and the denominator of the fraction.
x^{2}+\frac{3}{2}x+\frac{9}{16}=\frac{121}{16}
Add 7 to \frac{9}{16}.
\left(x+\frac{3}{4}\right)^{2}=\frac{121}{16}
Factor x^{2}+\frac{3}{2}x+\frac{9}{16}. 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{3}{4}\right)^{2}}=\sqrt{\frac{121}{16}}
Take the square root of both sides of the equation.
x+\frac{3}{4}=\frac{11}{4} x+\frac{3}{4}=-\frac{11}{4}
Simplify.
x=2 x=-\frac{7}{2}
Subtract \frac{3}{4} from both sides of the equation.