Solve for x
x = -\frac{17}{16} = -1\frac{1}{16} = -1.0625
x=\frac{1}{2}=0.5
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32x^{2}-17+18x=0
Add 18x to both sides.
32x^{2}+18x-17=0
Rearrange the polynomial to put it in standard form. Place the terms in order from highest to lowest power.
a+b=18 ab=32\left(-17\right)=-544
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as 32x^{2}+ax+bx-17. To find a and b, set up a system to be solved.
-1,544 -2,272 -4,136 -8,68 -16,34 -17,32
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 -544.
-1+544=543 -2+272=270 -4+136=132 -8+68=60 -16+34=18 -17+32=15
Calculate the sum for each pair.
a=-16 b=34
The solution is the pair that gives sum 18.
\left(32x^{2}-16x\right)+\left(34x-17\right)
Rewrite 32x^{2}+18x-17 as \left(32x^{2}-16x\right)+\left(34x-17\right).
16x\left(2x-1\right)+17\left(2x-1\right)
Factor out 16x in the first and 17 in the second group.
\left(2x-1\right)\left(16x+17\right)
Factor out common term 2x-1 by using distributive property.
x=\frac{1}{2} x=-\frac{17}{16}
To find equation solutions, solve 2x-1=0 and 16x+17=0.
32x^{2}-17+18x=0
Add 18x to both sides.
32x^{2}+18x-17=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{-18±\sqrt{18^{2}-4\times 32\left(-17\right)}}{2\times 32}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 32 for a, 18 for b, and -17 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-18±\sqrt{324-4\times 32\left(-17\right)}}{2\times 32}
Square 18.
x=\frac{-18±\sqrt{324-128\left(-17\right)}}{2\times 32}
Multiply -4 times 32.
x=\frac{-18±\sqrt{324+2176}}{2\times 32}
Multiply -128 times -17.
x=\frac{-18±\sqrt{2500}}{2\times 32}
Add 324 to 2176.
x=\frac{-18±50}{2\times 32}
Take the square root of 2500.
x=\frac{-18±50}{64}
Multiply 2 times 32.
x=\frac{32}{64}
Now solve the equation x=\frac{-18±50}{64} when ± is plus. Add -18 to 50.
x=\frac{1}{2}
Reduce the fraction \frac{32}{64} to lowest terms by extracting and canceling out 32.
x=-\frac{68}{64}
Now solve the equation x=\frac{-18±50}{64} when ± is minus. Subtract 50 from -18.
x=-\frac{17}{16}
Reduce the fraction \frac{-68}{64} to lowest terms by extracting and canceling out 4.
x=\frac{1}{2} x=-\frac{17}{16}
The equation is now solved.
32x^{2}-17+18x=0
Add 18x to both sides.
32x^{2}+18x=17
Add 17 to both sides. Anything plus zero gives itself.
\frac{32x^{2}+18x}{32}=\frac{17}{32}
Divide both sides by 32.
x^{2}+\frac{18}{32}x=\frac{17}{32}
Dividing by 32 undoes the multiplication by 32.
x^{2}+\frac{9}{16}x=\frac{17}{32}
Reduce the fraction \frac{18}{32} to lowest terms by extracting and canceling out 2.
x^{2}+\frac{9}{16}x+\left(\frac{9}{32}\right)^{2}=\frac{17}{32}+\left(\frac{9}{32}\right)^{2}
Divide \frac{9}{16}, the coefficient of the x term, by 2 to get \frac{9}{32}. Then add the square of \frac{9}{32} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+\frac{9}{16}x+\frac{81}{1024}=\frac{17}{32}+\frac{81}{1024}
Square \frac{9}{32} by squaring both the numerator and the denominator of the fraction.
x^{2}+\frac{9}{16}x+\frac{81}{1024}=\frac{625}{1024}
Add \frac{17}{32} to \frac{81}{1024} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(x+\frac{9}{32}\right)^{2}=\frac{625}{1024}
Factor x^{2}+\frac{9}{16}x+\frac{81}{1024}. 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}{32}\right)^{2}}=\sqrt{\frac{625}{1024}}
Take the square root of both sides of the equation.
x+\frac{9}{32}=\frac{25}{32} x+\frac{9}{32}=-\frac{25}{32}
Simplify.
x=\frac{1}{2} x=-\frac{17}{16}
Subtract \frac{9}{32} from both sides of the equation.
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