Solve 60x^2+5.88x-1.69=0

$$60 x ^ { 2 } + 5.88 x - 1.69 = 0$$

Solve for x

$$x=\frac{\sqrt{275109}}{3000}-0.049\approx 0.125836114$$

$$x=-\frac{\sqrt{275109}}{3000}-0.049\approx -0.223836114$$

Steps Using the Quadratic Formula

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.

$$60x^{2}+5.88x-1.69=0$$

This equation is in standard form: ax^{2}+bx+c=0. Substitute 60 for a, 5.88 for b, and -1.69 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.

$$x=\frac{-5.88±\sqrt{5.88^{2}-4\times 60\left(-1.69\right)}}{2\times 60}$$

Square 5.88 by squaring both the numerator and the denominator of the fraction.

$$x=\frac{-5.88±\sqrt{34.5744-4\times 60\left(-1.69\right)}}{2\times 60}$$

Multiply -4 times 60.

$$x=\frac{-5.88±\sqrt{34.5744-240\left(-1.69\right)}}{2\times 60}$$

Multiply -240 times -1.69.

$$x=\frac{-5.88±\sqrt{34.5744+405.6}}{2\times 60}$$

Add 34.5744 to 405.6 by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.

$$x=\frac{-5.88±\sqrt{440.1744}}{2\times 60}$$

Take the square root of 440.1744.

$$x=\frac{-5.88±\frac{\sqrt{275109}}{25}}{2\times 60}$$

Multiply 2 times 60.

$$x=\frac{-5.88±\frac{\sqrt{275109}}{25}}{120}$$

Now solve the equation x=\frac{-5.88±\frac{\sqrt{275109}}{25}}{120} when ± is plus. Add -5.88 to \frac{\sqrt{275109}}{25}.

$$x=\frac{\sqrt{275109}-147}{25\times 120}$$

Divide \frac{-147+\sqrt{275109}}{25} by 120.

$$x=\frac{\sqrt{275109}}{3000}-\frac{49}{1000}$$

Now solve the equation x=\frac{-5.88±\frac{\sqrt{275109}}{25}}{120} when ± is minus. Subtract \frac{\sqrt{275109}}{25} from -5.88.

$$x=\frac{-\sqrt{275109}-147}{25\times 120}$$

Divide \frac{-147-\sqrt{275109}}{25} by 120.

$$x=-\frac{\sqrt{275109}}{3000}-\frac{49}{1000}$$

The equation is now solved.

$$x=\frac{\sqrt{275109}}{3000}-\frac{49}{1000} x=-\frac{\sqrt{275109}}{3000}-\frac{49}{1000}$$

Steps for Completing the Square

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.

$$60x^{2}+5.88x-1.69=0$$

Add 1.69 to both sides of the equation.

$$60x^{2}+5.88x-1.69-\left(-1.69\right)=-\left(-1.69\right)$$

Subtracting -1.69 from itself leaves 0.

$$60x^{2}+5.88x=-\left(-1.69\right)$$

Subtract -1.69 from 0.

$$60x^{2}+5.88x=1.69$$

Divide both sides by 60.

$$\frac{60x^{2}+5.88x}{60}=\frac{1.69}{60}$$

Dividing by 60 undoes the multiplication by 60.

$$x^{2}+\frac{5.88}{60}x=\frac{1.69}{60}$$

Divide 5.88 by 60.

$$x^{2}+0.098x=\frac{1.69}{60}$$

Divide 1.69 by 60.

$$x^{2}+0.098x=\frac{169}{6000}$$

Divide 0.098, the coefficient of the x term, by 2 to get 0.049. Then add the square of 0.049 to both sides of the equation. This step makes the left hand side of the equation a perfect square.

$$x^{2}+0.098x+0.049^{2}=\frac{169}{6000}+0.049^{2}$$

Square 0.049 by squaring both the numerator and the denominator of the fraction.

$$x^{2}+0.098x+0.002401=\frac{169}{6000}+0.002401$$

Add \frac{169}{6000} to 0.002401 by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.

$$x^{2}+0.098x+0.002401=\frac{91703}{3000000}$$

Factor x^{2}+0.098x+0.002401. In general, when x^{2}+bx+c is a perfect square, it can always be factored as \left(x+\frac{b}{2}\right)^{2}.

$$\left(x+0.049\right)^{2}=\frac{91703}{3000000}$$

Take the square root of both sides of the equation.

$$\sqrt{\left(x+0.049\right)^{2}}=\sqrt{\frac{91703}{3000000}}$$

Simplify.

$$x+0.049=\frac{\sqrt{275109}}{3000} x+0.049=-\frac{\sqrt{275109}}{3000}$$

Subtract 0.049 from both sides of the equation.

$$x=\frac{\sqrt{275109}}{3000}-\frac{49}{1000} x=-\frac{\sqrt{275109}}{3000}-\frac{49}{1000}$$