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4x^{2}-8x+3=0
Divide both sides by 4.
a+b=-8 ab=4\times 3=12
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as 4x^{2}+ax+bx+3. To find a and b, set up a system to be solved.
-1,-12 -2,-6 -3,-4
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 12.
-1-12=-13 -2-6=-8 -3-4=-7
Calculate the sum for each pair.
a=-6 b=-2
The solution is the pair that gives sum -8.
\left(4x^{2}-6x\right)+\left(-2x+3\right)
Rewrite 4x^{2}-8x+3 as \left(4x^{2}-6x\right)+\left(-2x+3\right).
2x\left(2x-3\right)-\left(2x-3\right)
Factor out 2x in the first and -1 in the second group.
\left(2x-3\right)\left(2x-1\right)
Factor out common term 2x-3 by using distributive property.
x=\frac{3}{2} x=\frac{1}{2}
To find equation solutions, solve 2x-3=0 and 2x-1=0.
16x^{2}-32x+12=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{-\left(-32\right)±\sqrt{\left(-32\right)^{2}-4\times 16\times 12}}{2\times 16}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 16 for a, -32 for b, and 12 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-32\right)±\sqrt{1024-4\times 16\times 12}}{2\times 16}
Square -32.
x=\frac{-\left(-32\right)±\sqrt{1024-64\times 12}}{2\times 16}
Multiply -4 times 16.
x=\frac{-\left(-32\right)±\sqrt{1024-768}}{2\times 16}
Multiply -64 times 12.
x=\frac{-\left(-32\right)±\sqrt{256}}{2\times 16}
Add 1024 to -768.
x=\frac{-\left(-32\right)±16}{2\times 16}
Take the square root of 256.
x=\frac{32±16}{2\times 16}
The opposite of -32 is 32.
x=\frac{32±16}{32}
Multiply 2 times 16.
x=\frac{48}{32}
Now solve the equation x=\frac{32±16}{32} when ± is plus. Add 32 to 16.
x=\frac{3}{2}
Reduce the fraction \frac{48}{32} to lowest terms by extracting and canceling out 16.
x=\frac{16}{32}
Now solve the equation x=\frac{32±16}{32} when ± is minus. Subtract 16 from 32.
x=\frac{1}{2}
Reduce the fraction \frac{16}{32} to lowest terms by extracting and canceling out 16.
x=\frac{3}{2} x=\frac{1}{2}
The equation is now solved.
16x^{2}-32x+12=0
Quadratic equations such as this one can be solved by completing the square. In order to complete the square, the equation must first be in the form x^{2}+bx=c.
16x^{2}-32x+12-12=-12
Subtract 12 from both sides of the equation.
16x^{2}-32x=-12
Subtracting 12 from itself leaves 0.
\frac{16x^{2}-32x}{16}=-\frac{12}{16}
Divide both sides by 16.
x^{2}+\left(-\frac{32}{16}\right)x=-\frac{12}{16}
Dividing by 16 undoes the multiplication by 16.
x^{2}-2x=-\frac{12}{16}
Divide -32 by 16.
x^{2}-2x=-\frac{3}{4}
Reduce the fraction \frac{-12}{16} to lowest terms by extracting and canceling out 4.
x^{2}-2x+1=-\frac{3}{4}+1
Divide -2, the coefficient of the x term, by 2 to get -1. Then add the square of -1 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-2x+1=\frac{1}{4}
Add -\frac{3}{4} to 1.
\left(x-1\right)^{2}=\frac{1}{4}
Factor x^{2}-2x+1. 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-1\right)^{2}}=\sqrt{\frac{1}{4}}
Take the square root of both sides of the equation.
x-1=\frac{1}{2} x-1=-\frac{1}{2}
Simplify.
x=\frac{3}{2} x=\frac{1}{2}
Add 1 to both sides of the equation.