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3x^{2}+35x+1=63
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.
3x^{2}+35x+1-63=63-63
Subtract 63 from both sides of the equation.
3x^{2}+35x+1-63=0
Subtracting 63 from itself leaves 0.
3x^{2}+35x-62=0
Subtract 63 from 1.
x=\frac{-35±\sqrt{35^{2}-4\times 3\left(-62\right)}}{2\times 3}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 3 for a, 35 for b, and -62 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-35±\sqrt{1225-4\times 3\left(-62\right)}}{2\times 3}
Square 35.
x=\frac{-35±\sqrt{1225-12\left(-62\right)}}{2\times 3}
Multiply -4 times 3.
x=\frac{-35±\sqrt{1225+744}}{2\times 3}
Multiply -12 times -62.
x=\frac{-35±\sqrt{1969}}{2\times 3}
Add 1225 to 744.
x=\frac{-35±\sqrt{1969}}{6}
Multiply 2 times 3.
x=\frac{\sqrt{1969}-35}{6}
Now solve the equation x=\frac{-35±\sqrt{1969}}{6} when ± is plus. Add -35 to \sqrt{1969}.
x=\frac{-\sqrt{1969}-35}{6}
Now solve the equation x=\frac{-35±\sqrt{1969}}{6} when ± is minus. Subtract \sqrt{1969} from -35.
x=\frac{\sqrt{1969}-35}{6} x=\frac{-\sqrt{1969}-35}{6}
The equation is now solved.
3x^{2}+35x+1=63
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.
3x^{2}+35x+1-1=63-1
Subtract 1 from both sides of the equation.
3x^{2}+35x=63-1
Subtracting 1 from itself leaves 0.
3x^{2}+35x=62
Subtract 1 from 63.
\frac{3x^{2}+35x}{3}=\frac{62}{3}
Divide both sides by 3.
x^{2}+\frac{35}{3}x=\frac{62}{3}
Dividing by 3 undoes the multiplication by 3.
x^{2}+\frac{35}{3}x+\left(\frac{35}{6}\right)^{2}=\frac{62}{3}+\left(\frac{35}{6}\right)^{2}
Divide \frac{35}{3}, the coefficient of the x term, by 2 to get \frac{35}{6}. Then add the square of \frac{35}{6} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+\frac{35}{3}x+\frac{1225}{36}=\frac{62}{3}+\frac{1225}{36}
Square \frac{35}{6} by squaring both the numerator and the denominator of the fraction.
x^{2}+\frac{35}{3}x+\frac{1225}{36}=\frac{1969}{36}
Add \frac{62}{3} to \frac{1225}{36} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(x+\frac{35}{6}\right)^{2}=\frac{1969}{36}
Factor x^{2}+\frac{35}{3}x+\frac{1225}{36}. 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{35}{6}\right)^{2}}=\sqrt{\frac{1969}{36}}
Take the square root of both sides of the equation.
x+\frac{35}{6}=\frac{\sqrt{1969}}{6} x+\frac{35}{6}=-\frac{\sqrt{1969}}{6}
Simplify.
x=\frac{\sqrt{1969}-35}{6} x=\frac{-\sqrt{1969}-35}{6}
Subtract \frac{35}{6} from both sides of the equation.