Solve for x
x=\frac{3}{4}=0.75
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10x^{2}-11x+9-13x=-6x^{2}
Subtract 13x from both sides.
10x^{2}-24x+9=-6x^{2}
Combine -11x and -13x to get -24x.
10x^{2}-24x+9+6x^{2}=0
Add 6x^{2} to both sides.
16x^{2}-24x+9=0
Combine 10x^{2} and 6x^{2} to get 16x^{2}.
a+b=-24 ab=16\times 9=144
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as 16x^{2}+ax+bx+9. To find a and b, set up a system to be solved.
-1,-144 -2,-72 -3,-48 -4,-36 -6,-24 -8,-18 -9,-16 -12,-12
Since ab is positive, a and b have the same sign. Since a+b is negative, a and b are both negative. List all such integer pairs that give product 144.
-1-144=-145 -2-72=-74 -3-48=-51 -4-36=-40 -6-24=-30 -8-18=-26 -9-16=-25 -12-12=-24
Calculate the sum for each pair.
a=-12 b=-12
The solution is the pair that gives sum -24.
\left(16x^{2}-12x\right)+\left(-12x+9\right)
Rewrite 16x^{2}-24x+9 as \left(16x^{2}-12x\right)+\left(-12x+9\right).
4x\left(4x-3\right)-3\left(4x-3\right)
Factor out 4x in the first and -3 in the second group.
\left(4x-3\right)\left(4x-3\right)
Factor out common term 4x-3 by using distributive property.
\left(4x-3\right)^{2}
Rewrite as a binomial square.
x=\frac{3}{4}
To find equation solution, solve 4x-3=0.
10x^{2}-11x+9-13x=-6x^{2}
Subtract 13x from both sides.
10x^{2}-24x+9=-6x^{2}
Combine -11x and -13x to get -24x.
10x^{2}-24x+9+6x^{2}=0
Add 6x^{2} to both sides.
16x^{2}-24x+9=0
Combine 10x^{2} and 6x^{2} to get 16x^{2}.
x=\frac{-\left(-24\right)±\sqrt{\left(-24\right)^{2}-4\times 16\times 9}}{2\times 16}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 16 for a, -24 for b, and 9 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-24\right)±\sqrt{576-4\times 16\times 9}}{2\times 16}
Square -24.
x=\frac{-\left(-24\right)±\sqrt{576-64\times 9}}{2\times 16}
Multiply -4 times 16.
x=\frac{-\left(-24\right)±\sqrt{576-576}}{2\times 16}
Multiply -64 times 9.
x=\frac{-\left(-24\right)±\sqrt{0}}{2\times 16}
Add 576 to -576.
x=-\frac{-24}{2\times 16}
Take the square root of 0.
x=\frac{24}{2\times 16}
The opposite of -24 is 24.
x=\frac{24}{32}
Multiply 2 times 16.
x=\frac{3}{4}
Reduce the fraction \frac{24}{32} to lowest terms by extracting and canceling out 8.
10x^{2}-11x+9-13x=-6x^{2}
Subtract 13x from both sides.
10x^{2}-24x+9=-6x^{2}
Combine -11x and -13x to get -24x.
10x^{2}-24x+9+6x^{2}=0
Add 6x^{2} to both sides.
16x^{2}-24x+9=0
Combine 10x^{2} and 6x^{2} to get 16x^{2}.
16x^{2}-24x=-9
Subtract 9 from both sides. Anything subtracted from zero gives its negation.
\frac{16x^{2}-24x}{16}=-\frac{9}{16}
Divide both sides by 16.
x^{2}+\left(-\frac{24}{16}\right)x=-\frac{9}{16}
Dividing by 16 undoes the multiplication by 16.
x^{2}-\frac{3}{2}x=-\frac{9}{16}
Reduce the fraction \frac{-24}{16} to lowest terms by extracting and canceling out 8.
x^{2}-\frac{3}{2}x+\left(-\frac{3}{4}\right)^{2}=-\frac{9}{16}+\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}=\frac{-9+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}=0
Add -\frac{9}{16} to \frac{9}{16} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(x-\frac{3}{4}\right)^{2}=0
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{0}
Take the square root of both sides of the equation.
x-\frac{3}{4}=0 x-\frac{3}{4}=0
Simplify.
x=\frac{3}{4} x=\frac{3}{4}
Add \frac{3}{4} to both sides of the equation.
x=\frac{3}{4}
The equation is now solved. Solutions are the same.
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