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25x^{2}-20x+4-\left(3x-3\right)^{2}=0
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(5x-2\right)^{2}.
25x^{2}-20x+4-\left(9x^{2}-18x+9\right)=0
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(3x-3\right)^{2}.
25x^{2}-20x+4-9x^{2}+18x-9=0
To find the opposite of 9x^{2}-18x+9, find the opposite of each term.
16x^{2}-20x+4+18x-9=0
Combine 25x^{2} and -9x^{2} to get 16x^{2}.
16x^{2}-2x+4-9=0
Combine -20x and 18x to get -2x.
16x^{2}-2x-5=0
Subtract 9 from 4 to get -5.
a+b=-2 ab=16\left(-5\right)=-80
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as 16x^{2}+ax+bx-5. To find a and b, set up a system to be solved.
1,-80 2,-40 4,-20 5,-16 8,-10
Since ab is negative, a and b have the opposite signs. Since a+b is negative, the negative number has greater absolute value than the positive. List all such integer pairs that give product -80.
1-80=-79 2-40=-38 4-20=-16 5-16=-11 8-10=-2
Calculate the sum for each pair.
a=-10 b=8
The solution is the pair that gives sum -2.
\left(16x^{2}-10x\right)+\left(8x-5\right)
Rewrite 16x^{2}-2x-5 as \left(16x^{2}-10x\right)+\left(8x-5\right).
2x\left(8x-5\right)+8x-5
Factor out 2x in 16x^{2}-10x.
\left(8x-5\right)\left(2x+1\right)
Factor out common term 8x-5 by using distributive property.
x=\frac{5}{8} x=-\frac{1}{2}
To find equation solutions, solve 8x-5=0 and 2x+1=0.
25x^{2}-20x+4-\left(3x-3\right)^{2}=0
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(5x-2\right)^{2}.
25x^{2}-20x+4-\left(9x^{2}-18x+9\right)=0
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(3x-3\right)^{2}.
25x^{2}-20x+4-9x^{2}+18x-9=0
To find the opposite of 9x^{2}-18x+9, find the opposite of each term.
16x^{2}-20x+4+18x-9=0
Combine 25x^{2} and -9x^{2} to get 16x^{2}.
16x^{2}-2x+4-9=0
Combine -20x and 18x to get -2x.
16x^{2}-2x-5=0
Subtract 9 from 4 to get -5.
x=\frac{-\left(-2\right)±\sqrt{\left(-2\right)^{2}-4\times 16\left(-5\right)}}{2\times 16}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 16 for a, -2 for b, and -5 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-2\right)±\sqrt{4-4\times 16\left(-5\right)}}{2\times 16}
Square -2.
x=\frac{-\left(-2\right)±\sqrt{4-64\left(-5\right)}}{2\times 16}
Multiply -4 times 16.
x=\frac{-\left(-2\right)±\sqrt{4+320}}{2\times 16}
Multiply -64 times -5.
x=\frac{-\left(-2\right)±\sqrt{324}}{2\times 16}
Add 4 to 320.
x=\frac{-\left(-2\right)±18}{2\times 16}
Take the square root of 324.
x=\frac{2±18}{2\times 16}
The opposite of -2 is 2.
x=\frac{2±18}{32}
Multiply 2 times 16.
x=\frac{20}{32}
Now solve the equation x=\frac{2±18}{32} when ± is plus. Add 2 to 18.
x=\frac{5}{8}
Reduce the fraction \frac{20}{32} to lowest terms by extracting and canceling out 4.
x=-\frac{16}{32}
Now solve the equation x=\frac{2±18}{32} when ± is minus. Subtract 18 from 2.
x=-\frac{1}{2}
Reduce the fraction \frac{-16}{32} to lowest terms by extracting and canceling out 16.
x=\frac{5}{8} x=-\frac{1}{2}
The equation is now solved.
25x^{2}-20x+4-\left(3x-3\right)^{2}=0
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(5x-2\right)^{2}.
25x^{2}-20x+4-\left(9x^{2}-18x+9\right)=0
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(3x-3\right)^{2}.
25x^{2}-20x+4-9x^{2}+18x-9=0
To find the opposite of 9x^{2}-18x+9, find the opposite of each term.
16x^{2}-20x+4+18x-9=0
Combine 25x^{2} and -9x^{2} to get 16x^{2}.
16x^{2}-2x+4-9=0
Combine -20x and 18x to get -2x.
16x^{2}-2x-5=0
Subtract 9 from 4 to get -5.
16x^{2}-2x=5
Add 5 to both sides. Anything plus zero gives itself.
\frac{16x^{2}-2x}{16}=\frac{5}{16}
Divide both sides by 16.
x^{2}+\left(-\frac{2}{16}\right)x=\frac{5}{16}
Dividing by 16 undoes the multiplication by 16.
x^{2}-\frac{1}{8}x=\frac{5}{16}
Reduce the fraction \frac{-2}{16} to lowest terms by extracting and canceling out 2.
x^{2}-\frac{1}{8}x+\left(-\frac{1}{16}\right)^{2}=\frac{5}{16}+\left(-\frac{1}{16}\right)^{2}
Divide -\frac{1}{8}, the coefficient of the x term, by 2 to get -\frac{1}{16}. Then add the square of -\frac{1}{16} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-\frac{1}{8}x+\frac{1}{256}=\frac{5}{16}+\frac{1}{256}
Square -\frac{1}{16} by squaring both the numerator and the denominator of the fraction.
x^{2}-\frac{1}{8}x+\frac{1}{256}=\frac{81}{256}
Add \frac{5}{16} to \frac{1}{256} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(x-\frac{1}{16}\right)^{2}=\frac{81}{256}
Factor x^{2}-\frac{1}{8}x+\frac{1}{256}. 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{1}{16}\right)^{2}}=\sqrt{\frac{81}{256}}
Take the square root of both sides of the equation.
x-\frac{1}{16}=\frac{9}{16} x-\frac{1}{16}=-\frac{9}{16}
Simplify.
x=\frac{5}{8} x=-\frac{1}{2}
Add \frac{1}{16} to both sides of the equation.